COLOMBO, July 24 (Reuters) - Sri Lankan air force fighter jets bombed rebel positions on Thursday, the military said, as government forces continue their push against the rebels' northern stronghold.

The air raid on positions in the rebel-held districts of Mullaitivu and Kilinochchi came two days after the government dismissed a declaration by the Liberation Tigers of Tamil Eelam (LTTE) of a unilateral ceasefire from July 26 to August 4.

"Air force fighter jets attacked LTTE leaders gathering east of Thunukkai in Kilinochchi in the afternoon and a recruit training centre north of Oddusuddan in Mullaitivu this morning," said air force spokesman Wing Commander Janaka Nanayakkara.

"Pilots confirmed the targets were successfully engaged."

The military said fighting on Wednesday in four northern districts had killed 25 rebels and injured 21 Tiger rebels.

The military also said four solders died in the fighting and 10 were wounded.

The fighting comes a week after the military's claim it had dealt a "fatal blow" to the Tamil Tiger rebels, with the capture of the northwestern town of Vidattaltivu, the main base of the Tigers' sea wing and their logistics hub for the region.

Sri Lanka's government is pursuing a strategy to gradually retake the Tiger's northern stronghold and win the 25-year civil war amidst an almost daily barrage of land, sea and air attacks in northern rebel-held territories.

An email statement from the Tamil Tigers early on Tuesday said the rebels would refrain from military action during the 15th South Asian Association for Regional Cooperation (SAARC) conference from July 26 to Aug. 4.

But warned they would be forced to take "defensive action" if the military attacked them.

The government rejected the gesture. Sri Lanka's 2002 Norwegian-backed ceasefire pact with the Tamil Tigers formally ended in January after the government decided to scrap it, arguing the rebels were using it to buy time to regroup and rearm.

The civil war has killed more than 70,000 people since it started. The Tigers have been fighting for an independent state in north and east Sri Lanka for minority Tamils since 1983.

The Tigers were not immediately available for comment.

The government and rebels trade death toll claims that are almost impossible to verify independently. (Reporting by Ranga Sirilal; Editing by David Fogarty)

AlertNet news is provided by