Photographs from across Israel show how the Saturday morning attack from Gaza has upended life in Israel as far north as Tel Aviv.
The Israeli military said about 2,200 rockets have been launched from Gaza into Israel on Saturday since fighting began.
Those numbers contradict figures from Hamas military commander Muhammad Al-Deif, who previously said that 5,000 rockets had been launched.
To put that in context, some 4,000 rockets were fired from Gaza into Israel during the 50-day war between the two sides in 2014.
Reinforcements: Israel Defense Forces spokesman Rear. Admiral Daniel Hagari said in a statement that the military would reinforce southern Israel and the communities surrounding Gaza
"Numerous IDF soldiers, including special forces, have been dispatched to the area surrounding the Gaza Strip and are operating in a number of different locations in the division in order to protect the residents of southern Israel," the IDF said in a statement.
Palestinians have been barred from crossing checkpoints into Jerusalem from the West Bank since Hamas began its assault early Friday morning.
Some context: Such checkpoints controlling the movement of Palestinians has long been a point of contention.
Palestinians say such restrictions on their freedom of movement are humiliating and see them treated as second-class citizens.
Israel contends they are an important tool to combat militant incursions and terror attacks.
Israeli Emergency Services Magen David Alom said one of its staffers was killed and another four have been wounded in Hamas' early morning attack and incursion into Israel.
The group added that one of their vehicles has been taken into the Gaza Strip.
Israeli authorities earlier said at least 22 people have been killed, with more than 250 casualties.
Many details are still unclear about the assault, it is not yet known whether the 22 are civilians or military members.
Hamas said it captured Israeli soldiers near the Gaza border during its surprise attack Saturday morning.
In videos published by the militant group, at least three men dressed in civilian clothing were seen held at gunpoint. Hamas said the men were Israeli soldiers.
The Israel Defense Forces said it had no comment and CNN cannot verify Hamas’ claim.
Residents of two Israeli communities told the country's Channel 12 television station that assailants from Gaza are trying to break into their homes. They have repeatedly pleaded on television for assistance from the Israel Defense Forces.
One resident of Kibbutz Nir Oz told the broadcaster over the phone that his family, including two children ages 7 and 9, have barricaded themselves in a safe room while militants fired at the door.
Some background: A kibbutz is a type of self-sustaining community in Israel. Traditionally agrarian, the kibbutzim (plural for kibbutz) were more popular in the country's early years.
There are "large" numbers of Israel Police and Border Police responding to multiple locations and threats, police spokesman Dean Elsdunne said on Saturday.
Elsdunne said bomb squad technicians have been deployed to clear missile debris and shrapnel sites.
Elsdunne added that Police Commissioner Yaakov Shabtai is holding a "special situational assessment" at the national police headquarters in Jerusalem, which Israel Minister of National Security Itamar Ben Gvir is attending.
21 fronts: In a separate briefing, Shabtai said, “We are currently in a state of war, a complex attack in the area around Gaza, and the towns in southern Israel. Right now there are 21 active fronts in the south.”
Videos of the violence Saturday morning across Israel have begun to circulate online, giving the world a glimpse of the chaos on the ground.
Clips geolocated by CNN show militants firing on civilians in the southern Israel city of Sderot.
A video published by Reuters appears to show Palestinian gunmen dragging what looks like an Israeli soldier out of a tank. It is not known what condition the soldier is in, but the tank seems to be parked at a fence separating Gaza from Israel.
The tank is a Merkova, a battle tank used by the Israel Defense Forces.
The Hamas attack on Israel has been underway for about five hours, with sirens continuing to ring as far north as Tel Aviv and Jerusalem.
The sirens started ringing out early Saturday morning after rockets were fired from Gaza. They could still be heard as of of 12:30 p.m. local time.