Sri Lanka's military claimed last night to have moved to the brink of ending Asia's longest-running civil war by moving to within a few kilometres of the Tamil Tigers' last remaining hideouts, as the country prepared for a blitz of suicide attacks in retribution.

As tanks and helicopters claimed last night to be advancing through the jungle district of Mullaitivu and within kilometres of the strategic Elephant Pass in the north east, the government - fearing a wave of guerilla attacks in retribution - flooded the streets of the capital Colombo with military checkpoints and demanded that every Tamil resident in the city register their identities with police.

Last night, fresh from defeating the Tigers in their capital Kilinochchi, troops continuing through the jungle announced that they had entered a strategic township in Mullaitivu district, and were continuing to advance through the territory towards Mullaitivu town. A military source claimed, meanwhile, that another troops "were just two kilometers away" from Elephant Pass, 12km north of Kilinochchi.

Commanders have vowed to capture the Tamils’ rebel leader Velupillai Prabhakaran, who they believe is hiding in Mullaitivu town.

"Day by day, the Tigers' territory is shrinking and their numbers are dwindling. The objective of finishing this war won't be that long off," Major General Jagath Dias, commander of the battle for Kilinochchi, said.

As troops appeared to have moved to the brink of ending the 25 year civil war, Sri Lankan authorities and police put the capital Colombo, in the south, under virtual lockdown, with soldiers patrolling the streets and placing checkpoints by all major government, military, economic and tourist centres.

In a radio message, the authorities also reminded Colombo's Tamil residents of the city's controversial registration rules, whereby all residents from the north-east – mainly of Tamil extraction – face a possible year-long prison sentence if they fail to identify themselves to authorities in what the government says are security measures.

A retired senior government official told The Times that further tightening regulations on Sri Lanka’s three million Tamils risked fuelling anger and terrorist attacks, instead of ensuring security. The country's Tamil population say they have been the victim of decades of discrimination by the Sinhalese majority since Sri Lanka gained independence.

“People are made to suffer,” the official said. “People have to stand outside the police station in queues to register their details. They are treated like cattle, like dirt.”

Because of an almost total ban on all journalists travelling to the north-east, and curbs on aid groups, little is known about the scale of the humanitarian crisis caused by ongoing battles. In particular, the fate of hundreds of thousands of people who lived in the region remains unclear, with many said to have fled into the jungle ahead of troops’ advance while others are thought to reside in refugee camps in Vavuniya. An unknown number have been killed.

Analysts say that the battle against Tamil rebels is far from over, with the Tigers likely to return to classic guerrilla tactics – attempting to destroy the Sri Lankan economy through suicide bombings targeting economic, government and tourist centres.

The group, which is estimated to still have up to 1,900 fighters left, is also bolstered by a huge informer network among the three million Tamils living in Sri Lanka, who help it with weapons smuggling and suicide attacks.

“The LTTE (Tamil Tigers) will try their darndest with more bomb attacks in Colombo, in the south,” analyst Paikiasothy Saravanamuttu, of the Colombo-based Centre for Policy Alternatives, told The Times.

“They will want to hit economic targets, and they will want to show that they are still capable of inflicting great damage. The war is not over yet by any stretch of the imagination.”

However, he added that the government’s focus purely on military action, and its failure to seal any long-term reconciliation deal with Sri Lanka’s Tamil minority, would ensure long-term grievances within society remained in place.

“The main danger is that we snatch defeat away from the jaws of victory if we do not reach for a political settlement. The political dimensions are not being addressed,” he said.

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