Hamas’ armed wing said on monday that the militant group has been operating under new orders since june should israeli forces approach its locations in gaza. the announcement came just two days after the israel defense forces recovered the bodies of six hostages killed in gaza over the weekend.

The bodies were found in a tunnel under the Gazan city of Rafah. The hostages appear to have been killed between Thursday night and Friday morning, just hours before the Israeli army reached them, according to Israel’s National Institute of Forensic Medicine. Their autopsies indicated that they had all been shot at close range, apparently by execution.

Read more: Images from Israel where protesters blame Netanyahu for the deaths of hostages

Abu Ubaida, a spokesman for Hamas’s Al-Qassem Brigade, said the new instructions came into effect after Israel carried out a rescue operation in June that freed four hostages but killed dozens of Palestinians, including women and children.

Abu Ubaida did not provide details about the new instructions and said Hamas holds Israel responsible for the latest hostage deaths.

“Netanyahu’s insistence on releasing prisoners through military pressure, rather than a deal, means that they will be returned to their families in shrouds. Their families will have to choose whether they want them dead or alive,” he said.

A group representing the hostages’ families demanded that Netanyahu “address the nation and take responsibility.”

Read more: Families of Israelis held hostage by Hamas speak out

At a news conference on Monday, Netanyahu said the hostages had been shot in the back of the head and that he had asked their families for forgiveness. “I ask for forgiveness that we failed to bring them back alive,” he said. “Hamas will pay a very high price for that.”

Outrage erupted within Israel after news that six more hostages had been killed in Gaza. About half a million Israelis took to the streets on Sunday to express their anger and grief and demand a deal for the release of hostages.