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PHOTO: TOBIAS SCHWARZ/AFP/Getty Images
A policeman and firemen stand next to a truck on December 20, 2016 at the scene where it crashed into a Christmas market near the Kaiser-Wilhelm-Gedaechtniskirche (Kaiser Wilhelm Memorial Church) in Berlin. German police said they were treating as "a probable terrorist attack" the killing of 12 people when the speeding lorry cut a bloody swath through the packed Berlin Christmas market.
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Italian police and forensics experts gather around the body of suspected Berlin truck attacker Anis Amri after he was shot dead in Milan on December 23, 2016.  
The Tunisian man suspected of carrying out the deadly Berlin truck attack at the Christmas market was shot dead by police in Milan on December 23, Italy's interior minister Marco Minniti said. The minister told a press conference in Rome that Anis Amri had been fatally shot after firing at two police officers who had stopped his car for a routine identity check around 3:00 am (0200 GMT). Identity checks had established "without a shadow of doubt" that the dead man was Amri, the minister said. / AFP / DANIELE BENNATI        (Photo credit should read DANIELE BENNATI/AFP/Getty Images)
PHOTO: DANIELE BENNATI/AFP/AFP/Getty Images
Italian police and forensics experts gather around the body of suspected Berlin truck attacker Anis Amri after he was shot dead in Milan on December 23, 2016. The Tunisian man suspected of carrying out the deadly Berlin truck attack at the Christmas market was shot dead by police in Milan on December 23, Italy's interior minister Marco Minniti said. The minister told a press conference in Rome that Anis Amri had been fatally shot after firing at two police officers who had stopped his car for a routine identity check around 3:00 am (0200 GMT). Identity checks had established "without a shadow of doubt" that the dead man was Amri, the minister said. / AFP / DANIELE BENNATI (Photo credit should read DANIELE BENNATI/AFP/Getty Images)
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Police patrol inside the Christmas market area and past the destroyed booths two days after an attack with a truck in front of the Kaiser-Wilhelm-Gedaechtniskirche (Kaiser Wilhelm Memorial Church) in Berlin on December 21, 2016.
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PHOTO: ODD ANDERSEN/AFP/Getty Images
Police patrol inside the Christmas market area and past the destroyed booths two days after an attack with a truck in front of the Kaiser-Wilhelm-Gedaechtniskirche (Kaiser Wilhelm Memorial Church) in Berlin on December 21, 2016. German police on December 21, 2016 stepped up their hunt for the driver of a truck that ploughed through a Berlin Christmas market, in a deadly assault claimed by the Islamic State jihadist group.
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Federal prosecutor's office and the Federal Criminal Police Office ask for help with the reconnaissance to the attack on the Christmas market at the Berlin Memorial Church on December 19, 2016!

On December 19, 2016, a saddle truck type Scania, along with trailers with a Polish license plate, arrived at the entrance of the Christmas market at the Ged‰chtniskirche am Breitscheidplatz. The vehicle captured numerous people on the Christmas market and came to a halt after 60-80 meters on the Budapest road. According to a testimony, a person was removed from the vehicle shortly thereafter, and has since been fleeting.

The 24 year old Tunisian citizen Anis AMRI is urgently suspicious of this situation.
PHOTO: BKA
Federal prosecutor's office and the Federal Criminal Police Office ask for help with the reconnaissance to the attack on the Christmas market at the Berlin Memorial Church on December 19, 2016! On December 19, 2016, a saddle truck type Scania, along with trailers with a Polish license plate, arrived at the entrance of the Christmas market at the Ged‰chtniskirche am Breitscheidplatz. The vehicle captured numerous people on the Christmas market and came to a halt after 60-80 meters on the Budapest road. According to a testimony, a person was removed from the vehicle shortly thereafter, and has since been fleeting. The 24 year old Tunisian citizen Anis AMRI is urgently suspicious of this situation.
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BERLIN, GERMANY - DECEMBER 20:  The Brandenburg Gate stands illuminated in the colors of the German flag the day before a truck drove into a crowded Christmas market in the city center on December 20, 2016 in Berlin, Germany. So far 12 people are confirmed dead and 45 injured. Authorities have confirmed they believe the incident was an attack and have arrested a Pakistani man who they believe was the driver of the truck and who had fled immediately after the attack. Among the dead are a Polish man who was found on the passenger seat of the truck. Police are investigating the possibility that the truck, which belongs to a Polish trucking company, was stolen yesterday morning.  (Photo by Sean Gallup/Getty Images)
PHOTO: Sean Gallup/Getty Images
BERLIN, GERMANY - DECEMBER 20: The Brandenburg Gate stands illuminated in the colors of the German flag the day before a truck drove into a crowded Christmas market in the city center on December 20, 2016 in Berlin, Germany. So far 12 people are confirmed dead and 45 injured. Authorities have confirmed they believe the incident was an attack and have arrested a Pakistani man who they believe was the driver of the truck and who had fled immediately after the attack. Among the dead are a Polish man who was found on the passenger seat of the truck. Police are investigating the possibility that the truck, which belongs to a Polish trucking company, was stolen yesterday morning. (Photo by Sean Gallup/Getty Images)
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PHOTO: ODD ANDERSEN/AFP/Getty Images
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An ambulance and rescue workers arrive to the area after a lorry truck ploughed through a Christmas market on December 19, 2016 in Berlin, Germany. Several people have died while dozens have been injured as police investigate the attack at a market outside the Kaiser Wilhelm Memorial Church on the Kurfuerstendamm and whether it is linked to a terrorist plot.
PHOTO: Sean Gallup/Getty Images
An ambulance and rescue workers arrive to the area after a lorry truck ploughed through a Christmas market on December 19, 2016 in Berlin, Germany. Several people have died while dozens have been injured as police investigate the attack at a market outside the Kaiser Wilhelm Memorial Church on the Kurfuerstendamm and whether it is linked to a terrorist plot.
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Rescue forces stand in front of the truck that speed into a Christmas market in Berlin, on December 19, 2016 killing nine persons and injuring at least 50 people.
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PHOTO: JOHN MACDOUGALL/AFP/Getty Images
Rescue forces stand in front of the truck that speed into a Christmas market in Berlin, on December 19, 2016 killing nine persons and injuring at least 50 people. Ambulances and police rushed to the scene after the driver drove up the pavement of the market in a central square popular with tourists less than a week before Christmas, in a scene reminiscent of the deadly truck attack in Nice.
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 / AFP PHOTO / Don EMMERT        (Photo credit should read DON EMMERT/AFP/Getty Images)
PHOTO: DON EMMERT/AFP/Getty Images
Investigators inspect a truck following a shooting incident in New York on October 31, 2017. Several people were killed and numerous others injured in New York on Tuesday when a suspect plowed a vehicle into a bike and pedestrian path in Lower Manhattan, and struck another vehicle on Halloween, police said. A suspect exited the vehicle holding up fake guns, before being shot by police and taken into custody, officers said. The motive was not immediately apparent. / AFP PHOTO / Don EMMERT (Photo credit should read DON EMMERT/AFP/Getty Images)
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Story highlights

NEW: Mother says police should have apprehended suspect

ISIS-affiliated website releases video of Amri pledging allegiance to the group's leader

(CNN) —  

Video has emerged of Berlin Christmas market attack suspect Anis Amri pledging allegiance to ISIS. The footage appeared hours after the Tunisian man was killed in a Friday morning shootout with police in Milan, Italy.

The subject of a Europe-wide manhunt since Monday’s deadly market attack, Amri was stopped in Sesto San Giovanni, a district in the northeastern part of Milan, just after 3 a.m. local time, Italian police said on Twitter.

A video released on ISIS-affiliated website Amaq shows Amri pledging allegiance to the group’s leader, Abu Bakr al-Baghdadi, and vowing that “we will slaughter” the “crusaders who are shelling the Muslims every day.”

He does not refer to Monday’s attack that left 12 dead and injured 48, and it’s not clear when or where the video was recorded.

Who was Anis Amri?

The encounter that led to Amri’s death began when Italian police asked for his papers. When that happened, Amri pulled a .22-caliber gun out of his backpack and fired at them, police said.

Forensics experts gather around the body of Berlin atttack suspect Anis Amri on Friday in Milan.
PHOTO: DANIELE BENNATI/AFP/AFP/Getty Images
Forensics experts gather around the body of Berlin atttack suspect Anis Amri on Friday in Milan.

The driver of the police car returned fire, killing the 24-year-old suspect. A police officer, Cristian Morio, was shot in the encounter and is recovering in the hospital. A second officer, Luca Scata, was unharmed.

Two countries tried to deport him

Amri shouted, “Bastard cops,” before he was killed, according to Milan police Chief Antonio De Iesu.

Police Officer Cristian Movio was injured during Friday's shootout with Amri.
PHOTO: Courtesy Italian State Police
Police Officer Cristian Movio was injured during Friday's shootout with Amri.

At a press conference, Italian Interior Minister Marco Minniti said the slain man was Amri “without any doubt.” The Tunisian had previously lived in Italy.

The officers were not searching for him but stopped Amri as part of normal patrol operations, De Iesu said.

Nobody had alerted the police to Amri’s presence in the city.

Amri traveled from France, report says

Italian news agency ANSA said Amri came to Milan by train from the French region of Savoy.

A spokeswoman for the French anti-terrorism prosecutor’s office, Agnes Thibault Lecuivre, could not confirm the report, telling CNN the investigation was ongoing.

Milan police said Amri arrived at the city’s central station about 1 a.m. Friday.

If he did travel from France, Amri would have passed through at least two European borders after fleeing Berlin.

In response, Marine Le Pen, leader of France’s far-right National Front Party, criticized the European Union’s open borders policy as a “security disaster.”

German officials are working to determine whether Amri had a network of people helping him flee to Italy, German federal prosecutor Peter Frank said.

Amri was on threat list

Amri was considered to be one of the most dangerous Islamists in the country for months before Monday’s attack, according to German intelligence officials.

In March, he was put on a German security services list of dangerous people, which currently includes 549 individuals, the officials said.

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German Chancellor Angela Merkel said in a press conference that government ministers will be assessing what security measures need to be adapted in the wake of this week’s attack.