Israel launched new attacks against the Gaza City early Tuesday from air, ground and sea, and large sound of explosions was clearly heard.
The Israeli forces, backed by artillery and helicopters, rolled deeper into the densely populated part of the city, reports said.
Intense fighting broke out between Hamas fighters and Israeli troops in side the city. Al-Jazeera TV images showed that large explosions and the din of heavy machine gun fire were clearly heard and flashes of light lit up the skies.
Reports said Palestinian militants retreated and Israeli forces reached neighborhoods in the southern suburb of Gaza, where tens of thousands of Palestinians live.
Several buildings were on fire following explosions with thick smoke blanketing the area, witnesses said.
No exact numbers of casualties were available now, but reports said large number of deaths might be possible.
Some witnesses said that a batch of Israeli special forces advanced into the southern Gaza city and exchanged fire with Palestinian militants.
Hamas said it knocked out two Israeli tanks with rocket-propelled grenades, which was denied by the Israeli side.
The Israeli army has been carrying out air and ground military offensive in the enclave controlled by Hamas, where it bombed hundreds of targets that belong to the movement's political and military establishments.
Medics said Monday that over 900 people have been killed and more than 4,100 others wounded, around half of them are civilians. All Hamas political and military leaders have been hiding for 17 days in the Gaza Strip.
The deposed Hamas Prime Minister Ismail Haneya said in a recorded video on Monday night that Hamas is working on two parallel tracks, the first is resistance and steadfastness, the second is the political track to confront the military aggression on the Palestinian people.
Haneya's speech, the second one since the beginning of the Israeli military offensive on the enclave on Dec. 27 last year, was broadcast by the pro-Hamas al-Aqsa TV station.
(Xinhua News Agency January 13, 2009)