Israeli aircraft has struck at Palestinian militants in Gaza who responded with a volley of rockets which rained on southern Israeli towns, Israeli and Palestinian officials said.
Palestinian officials said on Saturday that nine militants were killed, while on the Israeli side one civilian was killed and four others were wounded.
Exchanges of fire are common between southern Israel and the Gaza strip controlled by the militant Hamas group, but this is the worst in months.
Gaza Health Ministry spokesman Adham Abu Salmia said nine people were killed and 15 wounded in separate attacks on militant targets.
Israeli police spokesman Micky Rosenfeld said one Israeli civilian was killed and four others wounded when Palestinian rockets exploded in residential areas in southern Israel.
An Israeli military spokesman confirmed a total of four strikes in Gaza, saying the military hit Palestinian militants from the Islamic Jihad, one of several groups in Gaza which fires rockets into southern Israel.
The spokesman said that the first attack specifically targeted a cell responsible for a Wednesday rocket attack that exploded deep inside Israel. That attack had caused no casualties.
The military "will not tolerate any attempt to harm Israeli civilians," the spokesman said. He spoke on condition of anonymity in accordance with military protocols.
The Israeli military released video footage taken from a military drone yesterday afternoon that shows Palestinians unloading rockets from a truck and preparing them for firing at Israel. The strike took place shortly afterward.
Abu Salmia, the Gaza health official, said five people had been killed and 11 wounded in the first attack. Islamic Jihad spokesman Abu Ahmed confirmed that one of its local field commanders, Ahmed Sheikh Khalil, was among the dead. He said Khalil was one of the group's chief bomb makers. "Today it was a great loss for us in the Islamic Jihad," he said.
"The size of our retaliation will equal our loss," it said in a text message sent to reporters.