Hamas, the Islamist movement that controls Gaza, said Thursday that it had arrested 10 people responsible for suicide bombings that killed three police officers in Gaza City on Tuesday.

The suspects, according to two Hamas security officials briefed on the investigation, included current and former members of Palestinian Islamic Jihad, a rival militant group that often works in concert with Hamas, especially against Israel.

The officials, who spoke on condition of anonymity because they were not authorized to discuss the investigation, said the suspects also belonged to an extremist movement, known as Salafi jihadism, that is at odds with the more moderate Hamas and has clashed repeatedly with it in recent years. Salafi jihadists view Hamas as insufficiently pious and overly interested in politics at the expense of violent struggle.

Read more: New York Times