Israel’s reliance on new Palestinian militias in Gaza to target Hamas was on display earlier this month when Hussam Al Astal, the leader of one of the groups, boasted about the killing of a police official in Hamas-controlled territory and said more such attacks are planned.
“We say to Hamas and everyone affiliated with Hamas: Just as we reached him, we will come for you, too,” said Astal in a video message that showed him brandishing an assault rifle.
Israel’s support for these pop-up militias is extensive. It provides air support from drones, and shares intelligence, weapons, cigarettes and food, according to Israeli officials and military reservists. Some militia members have been airlifted to Israeli hospitals after sustaining injuries, the officials said.
This partnership, born out of a shared enmity for Hamas, is a useful tool for Israel. With its forces limited by the terms of a cease-fire with the militant group, the militias can get to areas of Hamas-controlled territory that are supposed to be off-limits to Israeli troops, including Al Mawasi, where Hamas said Astal’s men killed the police official.
His group includes dozens of gunmen living in an Israeli-controlled part of Gaza. Hamas described the team that killed the official as “agents of the Israeli occupation.”
“The price of betrayal is heavy and costly,” Hamas said Thursday in a threat to militias working with Israel.
Astal denied receiving assistance from Israel other than food, saying his forces targeted the police official themselves. “He caused problems for people who wanted to come to us,” Astal told The Wall Street Journal in a phone interview. “He was harming us—anyone who tried to reach us was shot at or arrested. Whoever replaces him will be killed.”
Israel keeps close tabs on the militia’s activities and has stepped in to help or get them out of trouble in other cases.
“When they are going and doing activities against Hamas, we are there to watch them and some of the time to help,” said Yaron Buskila, who was a senior operations officer in the Israeli military’s Gaza division until the cease-fire came into effect in October. “It means helping them with information and if we see Hamas trying to threaten them or come close, we are actively getting involved.”
Buskila said he had no knowledge of the cooperation since he left that role. The Israeli military and Shin Bet domestic security agency declined to comment on cooperation with the militias.
In recent months, members of the Popular Forces, another Israeli-backed militia, were used to try to draw out trapped Hamas militants from tunnels inside Rafah, as Israel pumped explosives into the tunnels, a person familiar with the matter said.
Militia members have claimed responsibility for killing Hamas militants on social media, with graphic videos posted online. Others show militia members in Israeli tactical vests standing in formations and shooting rifles to upbeat music, as well as AI-generated drawings of a future Gaza. Some militias are recruiting new members in online posts.
An Israeli military reservist who was stationed in Gaza said he accompanied aid convoys supplying a militia in Rafah during the summer, which took place once a week late at night with the vehicle lights turned off. The aid and supplies included food, water, cigarettes and closed boxes with unknown contents that were placed in the vehicles by the Shin Bet security service, the reservist said.
Israel had to find other partners who work with them after Prime Minister Benjamin Netanyahu said during the war that he wouldn’t replace Hamas in Gaza with the Palestinian Authority. Early attempts to work with Gazan clans to form independent governance options for the enclave were quickly snuffed out by Hamas, which assassinated some of those potential partners.
Members of some militias have proved their ability to survive Hamas reprisals, forming several small communities in areas of Gaza under Israeli military control. Their numbers range from hundreds to thousands of people, according to militia leaders and Israeli and Arab officials.
So far the militias haven’t been able to turn themselves into a viable alternative to Hamas.
Some were involved in looting aid during the war and have a history of criminal activities, which makes many Gazans wary of supporting them. Nor have the militias had much success limiting the reach of Hamas, which has been able to reassert control over the less than 50% of Gaza it controls and is working on rebuilding its military structure.
The militias are also viewed as collaborators with Israel by many in Gaza.
Working with such armed militias has backfired in the past, say military analysts. Most notably, Israel’s support for the South Lebanon Army, a Christian militia, turned deadly when Israeli forces left Lebanon in 2000. Many SLA members were killed or forced to escape to Israel.
Another concern is that militias could ultimately turn on Israel.
“The interests of a militia are first of all to the militia, not to someone else. And it can turn on you,” said Saar Tzur, a recently retired senior officer in the Israeli military who served during the recent Gaza war.
It is unclear what happens to these militias if Israel pulls out of the half of Gaza it currently occupies. The second phase of President Trump’s peace plan calls for Israel to withdraw to a buffer zone around Gaza after Hamas is disarmed.
“They may occasionally conduct a successful operation against Hamas,” said Michael Milshtein, a former head of Palestinian affairs for Israeli military intelligence. But they may face a fate similar to Lebanon militias after the Israeli military withdrew, he said.
“It is a matter of time. They will have to choose whether to stay and be executed or arrested, or escape and join the IDF,” he said, referring to the Israel Defense Forces.
Write to Anat Peled at anat.peled@wsj.com and Dov Lieber at dov.lieber@wsj.com