Two Palestinians were hurt, one critically, in an Israeli air strike on Gaza City on Sunday, which the military said had targeted a senior Islamic Jihad militant.

Gaza emergency services spokesman Ashraf al-Qudra said the strike had hit a motorcycle in the northern neighbourhood of Saftawi, leaving its rider, a 22-year-old man, in critical condition.

A 12-year-old boy who was standing nearby suffered moderate head wounds in the raid, he told AFP.

Shortly afterwards, the Israeli army confirmed the strike, saying targeted a "senior operative" in the radical Islamic Jihad movement called Ahmad Saad whom it accused of planning an imminent attack on Israel.

"The IDF (Israel Defence Forces) successfully targeted a terrorist operative involved in recent attacks against Israel and was planning further attacks in the coming days," it said in a statement.

The strike had targeted Ahmad Saad, a "senior operative" with Islamic Jihad who specialised in rocket attacks and was behind several recent attacks on southern Israel.

"Saad is personally responsible for the launching of five rockets towards Ashkelon on January 16, 2014 which were intercepted by the Iron Dome missile defence system," said the army.

"The IDF operated in order to eliminate an imminent threat to the lives of Israeli civilians."

There was no confirmation from Gaza that the wounded man was Saad or that he belonged to Islamic Jihad, with sources in the radical movement also refusing to comment on the strike.

The morning strike followed another two overnight which came after a rocket hit southern Israel on Saturday, causing no damage or casualties.

On January 8, an Islamic Jihad militant was killed near Gaza City in what medics and family said was an Israeli drone strike, but the army denied any involvement.

Since the start of the year, tensions have risen in and around Gaza after a year of relative calm, with five people killed since December 20. Four of the victims were Palestinian and one was Israeli.

Since January 1, eight rockets fired from Gaza have landed in Israel with another five intercepted by Iron Dome last Thursday.