Around 200 Hamas activists had been trapped in the tunnels for months, according to Israeli and US officials, although some have since emerged and been killed in clashes with Israeli forces or have surrendered, Israeli media has reported.

Washington and other mediators had been seeking to reach a deal for the Hamas activists to lay down their arms in exchange for passage to other parts of the enclave, but those talks have faltered.

US special envoy Steve Witkoff had said the deal would be a test for a broader process to disarm Hamas across Gaza.

The killed activists included at least three local commanders, the Israeli military said on Thursday, as well as the son of one of Hamas’ exiled leaders, Ghazi Hamad.

Some Hamas sources confirmed the death of at least one commander, Mohammad Al Bawab, though the group has not officially confirmed the report.

Hamas has not officially confirmed the number of those trapped or how many may remain.

A spokesperson for the group in Gaza declined to comment on Israel’s alleged killing of the 40 gunmen.