Death toll from Gaza blasts rises to at least three - officials

Explosions hit two police checkpoints in Gaza City on Tuesday, killing three officers and wounding several other Palestinians, the Hamas-run interior ministry said, declaring a state of emergency after the blasts.

A Hamas interior ministry spokesman said security forces are making progress in their investigation to establish who was behind the blasts, but did not disclose further details.

A spokesman for the Israeli military said he knew of no involvement by Israel in the back-to-back incidents in Gaza city.

The first blast destroyed a motorcycle as it passed a police checkpoint with two riders aboard, witnesses said. 

Two policemen and a civilian were killed. It was not immediately clear if the riders were among the casualties.

The second explosion, less than an hour later, wounded several people at a police checkpoint elsewhere in the city, the interior ministry said. 

The ministry declared a state of emergency throughout Gaza, putting security forces on alert.

Hamas leader Ismail Haniyeh said everything is under control and the explosions will not undermine stability.

"Gaza will overcome all the conspiracies. They will not be able to do what they cannot accomplish with war and blockades," Haniyeh said in a statement.

Noting that those who are involved in the explosions will be found, Haniyeh said the security forces are able to overcome any conditions.

Hamas, which took control of Gaza in a 2007 civil war with the forces of Palestinian President Mahmoud Abbas, has at times faced internal opposition from more stringent militants aligned with al Qaeda or Daesh.