An Israeli airstrike on the Gaza Strip killed three Palestinians and wounded a fourth late Wednesday, said a spokesman for the territory's health ministry.

"Three civilians have been killed and another seriously wounded during an Israeli air raid to the east of the al-Maghazi refugee camp," in the centre of the Gaza Strip, ministry spokesman Achraf al-Qudra told AFP.

Two of those killed had been identified, he said: Khalil al-Jerba, aged 27, and 25-year-old Khaled al-Qerem.

Witnesses said the Israeli strike had targeted the car in which they were travelling.

An Israeli military spokeswoman confirmed the attack to AFP.

"The Israeli army targeted a group of terrorists who were preparing to fire rockets at Israel from the centre of the Gaza Strip," she said.

"This team has been implicated in the previous launching of rockets targeting communities in southern Israel."

In recent days, Palestinian militants have fired rockets into southern Israel from the Gaza Strip, without causing any casualties, according to the Israeli army.

A radical Salafist splinter group has claimed responsibility for some of the attacks.

Despite an informal truce between Hamas and Israel, tensions flare periodically on the Gaza-Israel border, with Palestinian militants firing rockets into the Jewish state and the Israeli military launching retaliatory air strikes on the Palestinian territory.

The last major flare-up was in June, when militants fired more than 150 rockets at southern Israel, wounding five people, and Israel hit back with air strikes that killed 15 Palestinians.