Brussels shooting: ISIS flag, ammo found in raid tied to Paris attacks

Updated 5:06 PM EDT, Wed March 16, 2016
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Story highlights

Two men questioned are let go without being charged, prosecutor's office says

Two suspects at large after raid on a Brussels apartment tied to Paris attacks, official says

NEW: Four people were arrested in Paris in terror plot raid, but authorities say no attack was imminent

(CNN) —  

The apartment raid turned up an ISIS flag, a Kalashnikov rifle and ammunition.

During the raid Tuesday, authorities killed suspect Belkhaid Mohammed, 35. The Algerian had not been on authorities’ radar before, spokesman Eric Van der Sypt said in a statement.

A sniper for the Belgian special forces killed Mohammed when he tried to open fire on police from a window.

His body was found next to a rifle and a book on Salafism, a puritanical branch of Islam that dictates only the followers of the Prophet Mohammed practice the correct Islam.

An intense manhunt followed Tuesday’s operation in the southern Brussels neighborhood of Forest. Authorities connected it to the investigation of the Paris terror attacks that killed 130 people in November.

One man was taken in for questioning during a subsequent house search Tuesday night in Brussels. And police also arrested an injured man who’d been taken to a hospital in Halle, a city about 12 miles (20 kilometers) south of Brussels.

But the Belgian federal prosecutor’s office said Wednesday that both men were later let go without being charged.

What happened

The raid Tuesday started when four Belgian and two French police officers arrived at what they thought was an empty residence in Forest, according to a senior Belgian counterterrorism official.

“From the moment that the door of the flat was opened, at least two persons … opened fire toward them,” Van der Sypt said.

Three officers – including a Frenchwoman – were hurt in the initial exchange of gunfire before managing “to retreat safely,” he said. A fourth officer from Belgium suffered a slight injury to the head in a later exchange.

Reinforcements arrived, with bullets flying back and forth for several hours.

Two of the four wounded officers already had been treated and released from an area hospital as of early Wednesday, according to Belgian Deputy Prime Minister Jan Jambon.

Afterward, authorities found another Kalashnikov in a building near the site of Tuesday’s raid. But other searches came up empty.

Belgian troops will help police in their anti-terrorism efforts, Prime Minister Charles Michel said.

There’s no change in Belgium’s threat level, now at its second highest. But Prime Minister Charles Michel acknowledged the raid underscored the need to be on guard.

“The terrorist threat level is maintained at level three as yesterday’s events confirm the threat is still real,” he said.

French arrests

Four people suspected of planning a terror attack were arrested Wednesday morning in Paris, French Interior Minister Bernard Cazeneuve said.

The four suspects, three men and a woman, were taken into custody.

A source close to the investigation told CNN that police moved in to make arrests in Paris after individuals discussed launching an attack in the city. So far the plot appears to be only aspirational in nature. Police have not recovered evidence pointing to concrete planning, the source told CNN.

Cazeneuve, speaking to French media, said intelligence services are making arrests and carrying out terror-related investigations every day and called for “prudence.” He confirmed that authorities found a starter pistol with one round but no other arms or weapons.

Belgium a focus after Paris attacks

It’s unknown what connection Tuesday’s raid has to the November 13 carnage in Paris. Belgium has been a focal point for investigators.

Belgium long has been a focal point for investigators.

European investigators focused intently on Belgium, especially Brussels, on the heels of the attack.

These two had an even more integral role than Abdelhamid Abaaoud – the man long identified as the ringleader of the attacks – according to the official.

In his remarks Wednesday, Van der Sypt noted that authorities have searched more than 100 houses and arrested 58 people as part of the post-Paris probe. Another 23 people have been arrested “in linked investigations.”

Attack suspect not target of latest raid, sources say

Abaaoud was killed during a dramatic raid that shook a Paris neighborhood and collapsed an entire floor of an apartment building.

Yet others with Belgian connections and ties to the November 13 attacks remain at large.

They include Abdeslam, a Belgian-born French national who lived and spent time with Abaaoud in a Belgian prison. The trail for Abdeslam, one of the few alleged Paris attackers to escape alive, went cold in December, according to a senior European counterterrorism official.

French sources close to the investigation said Abdeslam was not the target of Tuesday’s raid. (French police were part of that operation, according to those sources.)

There are many reason authorities investigating the Paris attacks are in Belgium. Many of those tied to the Paris attacks live in the country, and they’re believed to have met there before lashing out.

There is concern more individuals from the same place may be ready to launch other attacks.

CNN’s Steve Almasy, Paul Cruickshank, Stephanie Halasz and Nima Elbagir contributed to this report.