SCORES DIE IN ISRAELI AIR STRIKES !

Palestinians say Israeli F-16 bombers have launched a series of air strikes against key targets in the Gaza Strip, killing and injuring dozens of people.

Missiles destroyed security compounds run by the militant group Hamas in the centre of Gaza City, killing at least 120 people, Hamas officials said.

The strikes, the most intense Israeli attacks on Gaza in recent times, come after the expiry of a truce with Hamas.

Israel has threatened an offensive to stop the firing of rockets from Gaza.

Israel confirmed the strikes, saying they were launched in response to continued rocket fire by Palestinian militants against Israeli towns.

They targeted "Hamas terror operatives" as well as training camps and weaponry storage warehouses, the country's military said in a statement.

Hamas quickly vowed to carry out revenge attacks on Israel in response to the air strikes.

Reports of the casualties in Gaza mounted swiftly after news broke of the Israeli operation.

Palestinian militant group Hamas, which controls Gaza, initially said at least 40 people had been killed when a missile hit security headquarters in and around Gaza City.

That figure quickly rose, Hamas saying 120 were killed and some 400 people injured, the BBC Katya Adler reports from Jerusalem.

Medics in Gaza also reported high casualties, saying 120 people died in Gaza City and 23 in the southern city of Khan Younis, Reuters news agency said.

"Most security headquarters in Gaza were completely destroyed in the Zionist shelling," the Hamas-run al-Aqsa TV station said.

The air strikes are the most intense Israel has launched against Gaza for some time, and come amid rumours that that a ground operation is imminent.

Israeli security officials have been briefing about the possibility of a new offensive into Gaza for some days now, says the BBC's Paul Wood, in Jerusalem.

But most reports centred on the possibility of a ground offensive, and Prime Minister Ehud Olmert was not expected to authorise any operation until Sunday at the earliest.

BBC NEWS REPORT.