Israeli air force jets and gunboats have resumed bombardment of the Gaza Strip hitting 20 new targets, including a mosque in nearly twelve hours.

Israeli warplanes bombed the coastal enclave early Friday shortly after four rockets hit the Israeli city of Ashkelon.

The military claims it has targeted a cell responsible for launching the rockets on Ashkelon as well as the house of Muhammad Ma'tuk, a senior Hamas member in the northern Gaza city of Jabalya.

In a statement, the Israeli army said it bombed a mosque in Jabalya, alleging that the religious site was used for organizing attacks against Israel and storing Grad rockets.

Israel started its Operation Cast Lead on Saturday in which 428 Palestinians including women and children were killed and more than 2100 injured.

Tel Aviv says the attacks are aimed at stopping rocket attacks on Israeli communities; Hamas, however, has warned that the air raids would only intensify Palestinian groups' attacks.