With Israel vowing retaliation for the highest civilian death toll in Israel-held territory since Hamas’ Oct. 7 attack, diplomats rushed to prevent an escalation that could spiral into an all-out war after months of exchanges between Israel and Hezbollah over the border.

Weapons experts told The Associated Press that evidence appears to point to a rocket from Lebanon hitting the field. But they raised the possibility that the hit on civilians was an accident.

Here’s what we know and what remains unclear about the attack.

The strike left a crater about 2 meters (yards) wide, breaking through the carpet of artificial grass where the children were playing. Around it were scattered burned-out bicycles and scooters, some electric with their batteries melted. Walls of a nearby tent and shelter were pockmarked from shrapnel.

The Israeli military’s Chief of Staff Lt. Gene. Herzi Halevi said an Iranian-made Falaq rocket with a 53-kilogram (117-pound) warhead belonging to Hezbollah was used in the attack that landed in the town of over 11,000 inhabitants.

Israel released images of rocket fragments it said the military found, with visible lettering that matched pictures of Falaq rockets also provided by the military. The AP was unable to verify that the fragments were found on-site. No ordinance debris was visible when AP reporters visited Monday.

The Israeli military was investigating why the rocket wasn’t intercepted by its renowned missile defense system called Iron Dome.

While Iron Dome’s radar detected the launch, it did not release an interceptor missile to knock down the rocket, an Israeli military official told AP, speaking on condition of anonymity because of the sensitivity of the matter.

The military said the flight time may have been too brief. Hezbollah has experimented during the war with launching rockets from a shorter distance. The rocket was fired from just north of the Lebanese town of Chebaa, about 10 kilometers (6 miles) from Majdal Shams, it said.

The Iron Dome alert set off sirens at 6:18 pm Majdal Shams’ local council reported the rocket landed less than a minute later, leaving no chance for the children to run to shelters.

“At very short distance, you don’t have enough time to operate the Iron Dome,” said Yehoshua Kalisky, a senior researcher at the Institute for National Security Studies, a Tel Aviv think tank. Rockets fired from within 5 kilometers (3 miles) that take 2-3 seconds to reach their destination are nearly impossible to intercept, he said.

As a result, the interception rate along the northern border is considerably lower than in central Israel, where Iron Dome batteries have more time, he said.

Hezbollah, Lebanon’s most powerful military and political force, was quick to say it was not behind the attack, a rare denial from a group that normally claims every attack launched.

What Hezbollah would gain from attacking a Druze community is unclear. Many Druze in the Golan see themselves as citizens of Syria, Hezbollah’s ally. A strike on them could hurt the militant group’s standing — including with Druze in Lebanon — when it’s trying to keep support in the war.

An overt intentional strike on civilians would also be a dramatic escalation in Hezbollah’s near daily exchanges with Israel. The group’s officials have said they don’t aim to expand the war and will halt their strikes when a cease-fire is reached in Gaza.

In the thousands of rockets it has fired since October, Hezbollah has insisted it targets military and intelligence installations. Still, Hezbollah rockets have hit civilian areas. Before Saturday’s bloodshed, strikes had killed 13 civilians and 22 soldiers in Israel. In Lebanon, Israel’s attacks have killed more than 500 people, including 90 civilians.

Just before news of Saturday’s deadly attack emerged, Hezbollah claimed at least two strikes, using Katyusha rockets and the larger Falaq-1, targeting a military base on Mount Hermon, about 3 kilometers (2 miles) north of Majdal Shams.

Hezbollah-allied TV stations and news outlets were also quick to deny the group was behind the attack, questioning whether Israel was looking for an excuse to widen its war against Lebanon and the militant group amid the most serious push yet to achieve a cease-fire in Gaza.

Experts say the fragmentation and impact patterns are consistent with a rocket attack.

“The evidence that we can see from the ground, from impact site, is much more consistent with that of a rocket artillery of the type and size of the Falaq,” said Richard Weir, crisis and weapons researcher with Human Rights Watch.

The 53-kilogram (117-pound) warhead would explode on impact with a deadly high explosive load, causing irregular fragmentation.

Weir said the damage didn’t appear consistent with the scenario of a hit by an air defense missile that malfunctioned. Such missiles send regular-shaped fragments in every direction, and there was no sign of such fragmentation.

The shape of the crater and the direction a fence was blown down indicate the rocket came from the north, said Chris Cobb-Smith, a weapons analyst.

He said that without independent verification of the ammunition’s remnants it is impossible to say who is to blame.

Weir said a Hezbollah rocket aimed at the military position on Mount Hermon may have overshot its target, landing in Majdal Shams. He said any number of mistakes could have taken place, including a mechanical fault or human error in estimating the distance.

“These kinds of things happen even with the best trained forces, he said. “So it is possible that, given that this is an unguided piece of rocket, that this was a mistake.”

After Israel claimed Hezbollah was responsible for the blast, many Druze leaders in Lebanon, Syria and Israel spoke out against what they called an attempt to drive a wedge within the close-knit community over the strike. Followers of the Druze faith, which began as an offshoot of Shiite Islam, are divided between the three countries.

Some 300 Majdal Shams residents protested a visit by Israeli Prime Minister Benjamin Netanyahu on Monday, shouting that he was exploiting the bloodshed for political gain.

Only 20% of residents in Majdal Shams, part of the Golan Heights annexed by Israel in 1981, have accepted Israeli citizenship. Many still consider themselves citizens of Syria.

“For sure, it was not targeting Majdal Shams. There are many Israeli military bases around the town. I expected this threat was heading their way,” said Nabeeh Abu Saleh, a medic from the town who rushed to the scene Saturday.

Nothing prepared Abu Saleh, who has 25 years of experience as a medic, for what he saw. Some body parts were found 100 meters (yards) from the explosion. One of his nephews was killed, another injured.

The military said Iron Dome sirens have gone off in Majdal Shams 30 times during the conflict. A few months ago, a rocket landed short of the town, Abu Saleh said.

“We buried our children. We don’t want retaliation,” he said. “We have families in Lebanon, in Syria, and we have brothers here in Israel.”

El Deeb reported from Beirut.