Hamas said yesterday that two overnight bombings killed three Palestinian police officers in the Gaza Strip in what witnesses called suicide attacks as the Palestinian enclave was placed under a state of alert.

Witnesses told AFP that both bombings were suicide attacks by assailants on motorbikes, but there was no official confirmation.

A source familiar with the investigation said a Salafist movement in Gaza, which is run by Islamist movement Hamas, that sympathises with the Islamic State jihadist group was suspected.

Hamas’s interior ministry confirmed the three deaths, but spoke only of two “bombings” in Gaza City without providing details.

It said two of the police officers were 32 and the third was 45. Two separate police checkpoints were targeted, it said.

An investigation was underway as authorities pledged to track down the “masterminds”. New police checkpoints were set up in Gaza City.