Hamas warned on Monday that it would begin killing Israeli civilians held captive for every new Israeli bombing of civilian homes without warning.

The message came from Iran-backed Hamas’ armed wing spokesperson Abu Ubaida, who said Hamas has been complying and acting within Islamic instructions, keeping Israeli captives safe and sound. Hamas launched brutal attacks on Israel on Saturday, killing more than 250 at a music festival. 

Ubaida also blamed the threat on Israel’s increased bombing and killing of civilians who are in their homes by way of air strikes, without warning.

A spokesman for the Al-Qassam Brigades told Al-Jazeera in an interview that it would begin killing a single hostage for each Israeli airstrike that lands in Gaza without warning.

The spokesman also said executions would be recorded and broadcast to the public.

Israel has carried out over a thousand airstrikes in Gaza since the Hamas attack on Saturday.

Reuters contributed to this report.