Among the rubble of the United Nations-run al-Sardi school in central Gaza’s Nuseirat refugee camp were the remnants of the weapons that killed at least 40 Palestinians.

The Israeli attack in the early hours of Thursday gave the displaced people sheltering in the school no prior warning. Fourteen children were killed, as well as nine women and at least 74 other people were wounded. The weapons used to carry out the attack – according to an Al Jazeera analysis of the fragments left behind – were US-made.

An inertial measurement unit from the missile, used to aid with precision targeting, was manufactured by Honeywell, an American conglomerate that specialises in the design and delivery of sensors and guidance devices that are used in a variety of military weapons.

Al Jazeera’s Sanad verification unit discovered that one of the fragments found in Nuseirat bore the manufacturer and category number HG1930BA06, tracing it back to Honeywell. HG1930 refers to the specific sensor manufactured by the company.

The same part was found after the Israeli bombing of a Palestinian home in Shujayea, Gaza in 2014. The two pieces, in the most recent and the 2014 bombing, have the same manufacturer part number inscribed on them.

“We see also other numbers like the MFR, HG 1930 and then BA 06. This is the manufacturer part number that provides more specific details about the component of the missiles,” Elijah Magnier, an independent military and political analyst, told Al Jazeera. “Now, if you look at the manufacturer identification … it is a format used by the aerospace and defence sector in the United States connected to Honeywell.”

“Honeywell is known for the supply of IMU in the various military applications, and particularly the guided missiles that it has been providing to the Israeli Air Force since the year 2000.”

Al Jazeera has reached out to Honeywell for comment, but has yet to receive a response.

Israeli attacks on UN spaces have become commonplace during Israel’s war on Gaza, which has now killed more than 36,000 Palestinians.

The United States has been criticised for its role in supporting Israel, and particularly its continued supply of weapons.

Major rights groups have repeatedly accused Israel of violating international law, and Israel is currently facing a genocide case at the International Court of Justice. The International Criminal Court’s chief prosecutor has also sought arrest warrants for Prime Minister Benjamin Netanyahu and Defence Minister Yoav Gallant for their actions in Gaza.

In May, a US government report found possible Israeli violations of international law in Gaza, but stopped short of identifying the violations that would end its continuing military aid. US President Joe Biden has threatened to stop the supply of some offensive weapons to Israel if it continues its Rafah operation, but has not carried out the threat, despite Israel pressing on in the area, which lies in southern Gaza.

Central Gaza under attack

Central Gaza has most recently come under severe Israeli bombardment, which Palestinians have described as similar to the early days of the war.

The attack on al-Sardi school in Nuseirat is part of that assault.

“The bombardment came from here,” said Naim al-Dadah, a survivor of the attack.

“We were sleeping. The flying metal reached the roof on the other side and all these nets landed over there, on the other side. What happened to us is beyond anyone’s imagination.”

Other witnesses say the attack tore people to pieces. Survivors collected body parts, including those of many children, until the early hours of the morning. Weapon debris was scattered throughout shattered rooms and the blood-stained mattresses. Multiple rooms were targeted, though the building’s structure remained intact.

Israel’s Arabic language spokesperson Avichay Adraee, claimed the UN school was targeted because it housed a Hamas command post and fighters involved in the Palestinian group’s October 7 attack on Israel, which killed 1,139 people. He also claimed Israel took several steps to minimise the possibility of civilian casualties. The director of Hamas’s government media office, Ismail al-Thawabta, rejected Israel’s claims.

In April, the media outlet +972 Magazine reported that Israel uses an artificial intelligence-targeting system called Lavender in its Gaza-bombing campaign. The report quoted Israeli military officials who said that the system generates targets to kill. For low-level Hamas targets, the report said, the army was permitted to kill 15 to 20 civilians. An attack on a more senior Hamas official with the rank of battalion or brigade commander was used to justify the killing of more than 100 civilians.