JERUSALEM: Three loud explosions rocked Jerusalem shortly after air raid sirens wailed across the city on Tuesday night, AFP correspondents said.
The sirens sounded at about 1900 GMT, with at least four bright flashes lighting the sky southwest of the city, a correspondent said.
The attack was claimed by the Ezzedine al-Qassam Brigades, the armed wing of Hamas, which said it had fired four M75 rockets at Jerusalem.
"For the first time, the Qassam Brigades strike Haifa with an R160 rocket, and strike occupied Jerusalem with four M75 rockets," it said.
Witnesses reported hearing a loud explosion in Ramat Raziel, southwest of the city, although there was no immediate confirmation from police or the army.
The Israeli army had no immediate comment on the attack, nor was there any immediate confirmation of anything hitting the northern port city of Haifa, which lies around 160 kilometres (100 miles) from the Gaza Strip.
The rocket fire occurred as Israel began a waging major campaign against Hamas militants in the Gaza Strip.
Media reports also spoke of sirens sounding north of Tel Aviv for the first time as Hamas militants stepped up their battle against Israel.