Sri Lankan attack helicopters bombed Tamil Tiger positions in the north of the island on Saturday, the military said, a day after ground forces seized the rebel headquarters town of Kilinochchi.
The military is now targetting the port town of Mullaitivu and other rebel strongholds in the north as it presses on with the deepest push into rebel-held areas to bring an end to the 25-year separatist war.
There has been no coment from the Liberation Tigers of Tamil Eelam on the fall of Kilinochchi, for long the centre of the Tamil fight for an independent homeland in which more than 70,000 people have been killed.
"MI-24 helicopters attacked rebel positions west of Mullaitivu in support of ground troops," said a military source asking not to be named in line with national security policy.
Troops fought their way into the Tiger stronghold of Kilinochchi deep in the north on Friday, in one of the biggest blows for the rebels in years.
Details of casualties from the fighting have not yet emerged and a pro-rebel web site www.tamilnet.com said the Tigers had moved their headquarters further northeast before the town fell.
"The Sri Lanka Army (SLA) has entered a virtual ghost town," the website said. "The Tigers, who had put up heavy resistance so far, had kept their casualties as low as possible in the defensive fighting."
Sri Lanka military spokesman Brigadier Udaya Nanyakkara said troops were carrying out search and recovery operations in Kilinochchi town on Saturday.
Security has been tightened across the island following a suicide bombing that killed three air force personnel in the capital Colombo shortly after President Mahinda Rajapaksa announced the fall of the de facto rebel capital.
Military officials say the rebels have in the past hit back with suicide bombings in the capital and elsewhere whenever they have come under pressure on the northern frontlines.
"We will take all possible measures to avert any more terrorist attacks, they (LTTE) are desperate now with the biggest defeats in northern war front so they will try more attacks," said Nanyakkara.
The LTTE started fighting the government in 1983. It says it is battling for the rights of minority Tamils in the face of mistreatment by successive governments led by the Sinhalese majority since Sri Lanka won independence from Britain in 1948.
Exactly a year ago, Rajapaksa's government formally scrapped an increasingly tattered six-year truce brokered by Norway, saying the rebels were using it as cover to regroup and re-arm.
The military had been closing in on Kilinochchi since September. Over the past month, it has been assaulting Tiger defences encircling the town and both sides have claimed to have inflicted ever higher death tolls on the other.
"It was the constant dream of all Sri Lankans, whether Sinhala, Tamil or Muslim, who are opposed to separatism, racism, and terrorism, and have always, sought peace, freedom and democracy," Rajapaksa said in a nationally televised address on Friday.
"Today our heroic troops have made that dream a reality. A short while ago, our brave and heroic troops have fully captured Kilinochchi that was considered the main bastion of the LTTE."
In Washington, State Department spokesman Gordon Duguid said the Tamil Tigers had been "one of the most notorious and brutal terrorist organizations over the past 20 years" but he urged the government to address Tamil concerns.
"A peaceful dialogue is what is called for to resolve the differences and legitimate concerns of the Tamils," he said.