GAZA CITY // Israel kept up its offensive in southern Gaza today, as its air force carried out threatened strikes on suspected arms-smuggling tunnels in Rafah on the Egyptian border, witnesses said. Israel carried out 60 airstrikes overnight after the first day of a three-hour ceasefire for humanitarian aid. Bombing continued in the north of the densely populated coastal strip, with three people wounded when Al Taqwa mosque was destroyed in an air strike in Gaza City late yesterday, medics said. In a new development, four rockets hit northern Israel from Lebanon early today, military sources said. Five people were slightly wounded when the projectiles fell around the area of the northern town of Nahariya, Israeli media reported. In Rafah, warplanes hit a house and a suspected tunnel in an open area near the Egyptian border around 1am local time, witnesses said. Four missiles struck open ground shortly after 3am, they added. The army confirmed that strikes were taking place in Rafah. There were no reports of casualties. Yesterday afternoon, Israeli planes dropped tens of thousands of leaflets on the Rafah area, warning people to leave their houses or face air strikes. People were told that they could return to their homes at 8am today. The Rafah area is crisscrossed by what the Israeli army estimates to be some 300 tunnels and what residents have said are 500 subterranean passages from Gaza into Egypt. They are used to smuggle supplies and arms into Gaza, an impoverished enclave that Israel has virtually locked down since Hamas seized power in June 2007. Ending the smuggling is a key element of the ceasefire plan proposed by the Egyptian president Hosni Mubarak. Meanwhile, witnesses reported that Israeli tanks had entered southern Gaza. The army would neither confirm nor deny the claim. There were also reports that there had been three air strikes on open areas near the southern city of Khan Yunis and several in northern Gaza. Just before dawn, witnesses said, an air strike destroyed the home of Mohammed al Sinwar, a senior commander of Hamas's armed wing, the Ezzedine al Qassam Brigades, in Khan Yunis. No casualties were reported. The defence minister Ehud Barak had been given the green light by Israel's security cabinet yesterday to order a deeper offensive into Gaza as part of the campaign to halt Hamas cross-border rocket attacks. But he also decided to send an envoy to Cairo today to get details on an Egyptian ceasefire plan, which secured widespread international backing amid rising concern about the scale of the civilian casualties. Israeli shelling and air attacks around Gaza City were halted for three hours yesterday afternoon as a humanitarian gesture. Hamas also halted rocket attacks. People and cars quickly filled the streets of Gaza City, and long queues formed outside bakeries, which soon ran out of bread. Aid groups sent dozens of truckloads of food and fuel across the border during the truce. But the fighting quickly resumed, inflicting new deaths. A man, his three sons and a nephew were killed in one attack at the Jabaliya refugee camp and an air strike killed two men in Khan Yunis Wednesday night, medics said. Witnesses said the pair belonged to Hamas. Islamic Jihad said warplanes destroyed the homes of three of its military commanders, without causing casualties. The Israeli offensive, which began Dec 27, has so far killed 702 Palestinians and wounded 3,100, according to Gaza medics. Hundreds of Hamas rockets fired into Israel over the past 12 days have killed four people, including an Israeli soldier, and wounded dozens. Six Israeli soldiers have died in combat. Israel previously fought a 34-day war with Lebanon's Hizbollah militia in 2006, after guerrillas from the Lebanese Shiite movement seized two Israeli soldiers in a deadly cross-border raid. During the conflict, Hizbollah sent more than 4,000 rockets into northern Israel. The war killed more than 1,200 Lebanese, mostly civilians, and more than 160 Israelis, mostly soldiers. Israel is currently in the 13th day of a massive offensive in the Gaza Strip. Hizbollah carried out its deadly raid in 2006 two weeks into Israel's last major operation in Gaza, started after Gaza militants seized another Israeli soldier in a raid near the Palestinian territory. * AFP