Israel Used 2,000-Pound Bombs in Strike on Jabaliya, Analysis Shows

Israel used at least two 2,000-pound bombs during an airstrike on Tuesday on Jabaliya, a dense area just north of Gaza City, according to experts and an analysis conducted by The New York Times of satellite images, photos and videos.

Hospital officials said that dozens of civilians were killed and hundreds wounded in the strike. Israel said it was targeting a Hamas commander and fighters, as well as the network of underground tunnels used by Hamas, the militant group that controls Gaza, to hide weapons and fighters.

Israel’s use of such bombs, the second largest type in its arsenal, is not uncommon, and the size is generally the largest that most militaries use on a regular basis. They can be used to target underground infrastructure, but their deployment in a dense and heavily populated area like Jabaliya has raised questions of proportionality — whether Israel’s intended targets justify the civilian death toll and destruction its strikes cause.

The evidence and analysis show that the Israeli military dropped at least two 2,000-pound bombs on the site. Two impact craters are about 40 feet wide — dimensions consistent with underground explosions that this type of weapon would produce in light, sandy soil, according to a 2016 technical study by Armament Research Services, a munitions research consultancy.

Marc Garlasco, one of the study’s authors, said that the bombs might have had “a delay fuse,” which delays detonation until milliseconds after penetration of the surface or a building so that the explosion’s destructive power reaches more deeply.

The bombs are usually outfitted with guidance kits called Joint Direct Attack Munitions, turning them from so-called dumb bombs into precision, GPS-guided weapons.

Mr. Garlasco, who works as a military adviser for the Dutch organization PAX, said it was unclear from visuals alone whether the bombs were equipped with bunker-busting warheads, which are designed to pierce through reinforced military structures. But Israel’s publicly stated objective was to target a Hamas leader in an underground bunker.

Without access to the strike site, The Times was not able to determine whether there were tunnels below.

The only larger bomb in Israel’s arsenal is 4,500 to 5,000 pounds, according to Jeremy Binnie, the Middle East and Africa editor for the defense intelligence firm Janes.

Eighty-three countries, including the United States but not Israel, have signed a commitment to refrain “as appropriate, from the use of explosive weapons in populated areas” because of their likelihood of harming civilians.

“Israel’s continual bombardment of Gaza, including this Jabaliya strike, magnifies this concern many times over,” said Omar Shakir, the Israel and Palestine director at Human Rights Watch.

The Israeli military has declined to comment on the number and specific type of weapons it used in Jabaliya. Its public messaging around its repeated strikes on Jabaliya this week, however, has led to some confusion.

In social media posts, the Israeli military claimed that a strike video showed the killing of the head of Hamas’s Anti-Tank Missile Unit on Wednesday. But The Times determined that the footage in fact captured the strike on Jabaliya on Tuesday, which Israel claimed killed a different commander. The military declined to comment on the reason for the discrepancy.