Air bombardments and rocket fire between Israel and Gaza intensified Thursday after Israeli air strikes killed three senior Hamas commanders overnight.
The Israeli military said its forces pounded rocket installations in the Gaza Strip as dozens of rockets landed in southern Israel.
Israel said more than 200 Hamas rockets had been fired at Israel and its forces had targeted more than 100 rocket installations in Gaza since a temporary cease-fire collapsed on Monday.
Israel, Hamas confirms death of commanders
Hamas identified those killed as Mohammed Abu Shamaleh, Raed al-Attar and Mohammed Barhoum. Israeli Defense Minister Moshe Yaalon said the three "were responsible for deadly attacks" against Israel, including the killing of Israeli soldiers and the 2006 kidnapping of soldier Gilad Shalit.
Yaalon called the assassination of the three commanders "a very important intelligence and operational achievement by the Israeli army and the Shin Bet security service" and that Israel would continue to target other Hamas leaders.
The funeral procession for the commanders drew thousands of Palestinians into the streets of Gaza, with some firing guns into the air. Hamas spokesman Sami Abu Zuhri said the successful Israeli attack would not deter the militants.
"The assassination of the al-Qassam leaders in Rafah is a big Israeli crime that will not succeed in breaking the will of our people and won't weaken the resistance. And the occupation will pay the price, God willing," he warned.
An Israeli military spokeswoman said aircraft carried out 20 assaults in Gaza on Thursday. Late on Tuesday Israel targeted Hamas's top military commander, Mohammed Deif, but failed to kill him. Deif's wife and seven-month-old son were killed in the air strike, Hamas said.
Netanyahu vows more strikes
Following a meeting of his security ministers Wednesday night, Israeli Prime Minister Benjamin Netanyahu told a news conference that the operation against Gaza would continue. He said only the guarantee of the calm and safety of Israeli citizens will bring an end to this operation adding that "therefore we are talking about a long and continuing campaign."
Netanyahu said Hamas leaders were not only legitimate targets but targets of high priority.
Hamas spokesman Sami Abu Zuhri retorted that the threat reflected the extent of Israel's violence and lack of seriousness in achieving a cease-fire.
He said the threats would not frighten Hamas leaders and that "on the contrary, we will continue to protect and defend our people in facing Israeli crimes."
Hamas' military wing threatened to launch attacks against Israel's main airport near Tel Aviv Wednesday night, but the airport appeared to be operating normally Thursday.
Each side accuses the other of breaking the temporary cease-fire Monday after 10 days of negotiations and calm.
Some progress had been reported in the talks, brokered by Egypt, to discuss a permanent truce. But the two sides remained far apart on their principal demands.
Hamas wants Israel to end the seven year-old blockade of Gaza while Israel wants all militant groups in Gaza to disarm.
During the six weeks of violence more than 2,000 Palestinians have been killed, most of them civilians according to Palestinian authorities. On the Israeli side, 64 soldiers and three civilians have been killed.
The United Nations Security Council expressed "grave concern" Wednesday at the resumption of violence, which had paused for a 10-day cease-fire and peace talks. All 15 council members urged both sides to again halt the fighting and return to negotiations on a long-term truce.
Some information for this report provided by Reuters.
Smoke and dust billow in the distance after an Israeli strike hit Gaza City, northern Gaza Strip, Thursday, Aug. 21, 2014.
A wounded man is evacuated from the scene of an air strike in Gaza City, Aug. 21, 2014.
Palestinians overcome by emotion arrive at a mosque for shelter after an Israeli strike hit Gaza City, northern Gaza Strip, Thursday, Aug. 21, 2014.
The mother of a Palestinian Hamas militant killed in an Israeli air strike mourns as she looks at his body during his funeral in Jabaliya in the northern Gaza Strip, Aug. 21, 2014.
People pray next to the bodies of Palestinians killed in Israeli air strikes during their funeral at a mosque in Gaza City, Aug. 21, 2014.
Sunrise over Gaza, Aug. 21, 2014.