TIMELINE: Israeli-Hamas violence since truce ended

(Reuters) - Israeli forces hit the Gaza Strip from land, sea and air on Saturday, stepping up their offensive against Hamas in the Palestinian enclave as tanks and troops waited on the border for a possible ground offensive.

Here is a timeline of events since Hamas ended a truce earlier in December:

December 14 - Hamas leader Khaled Meshaal says the group will not renew a six-month-old truce with Israel.

December 18 - Hamas declares the end of the Egyptian-brokered ceasefire, which expires the next day with a surge of cross-border fighting.

December 24 - Gaza Palestinian militants ratchet up rocket fire toward Israel.

December 27 - Israel launches massive air strikes on Gaza in response to the intensified rocket and mortar fire killing at least 229 Palestinians.

December 28 - Hamas says an Israeli air strike destroys a laboratory building at the Islamic University, a significant cultural symbol of Hamas.

-- Israeli aircraft bomb some 40 smuggling tunnels in the Gaza Strip that provide a lifeline to the outside world.

December 29 - Israel steps up its air strikes and bombs the Hamas-run Interior Ministry, the first air strike targeting a government building in the offensive.

-- Israel declares areas around the Gaza Strip a "closed military zone."

-- Palestinian militants fire rockets deeper into southern Israel.

December 30 - Israeli warplanes press on for the fourth day with attacks on Hamas targets.

-- Hamas spokesman Fawzi Barhoum urges Palestinian groups to respond using "all available means" against Israel.

-- Israel says its attacks herald "long weeks of military action."

December 31 - Hamas leader Ismail Haniyeh tells Palestinians that "victory is near."

-- Emergency session of U.N. Security Council to consider resolution drafted by Arab countries calling for immediate ceasefire adjourns without a vote.

January 1 - Israel kills Nizar Rayyan, a hardline Hamas leader, in an air attack on his Gaza Strip home.

-- Palestinian casualties since December 27 are 412 dead and about 1,850 wounded. A U.N. agency says about a quarter of the dead are civilians.

-- Three Israeli civilians and a soldier have been killed by Palestinian rockets since the air strikes began.

January 2 - No sign of a ceasefire on the seventh day of the conflict, with at least 429 Palestinians killed and 2,000 wounded, but a Palestinian official says that Egypt had begun exploratory talks with Hamas to halt the bloodshed.

January 3 - An air strike on a mosque kills 11 Palestinian civilians and wounds dozens, as Israeli tanks and troops wait on the border for a possible ground offensive. Palestinian death toll rises to at least 446.