Sri Lanka's government has decided to annul a six-year ceasefire agreement with the Tamil Tigers.
The truce has been dead since a new phase of a two-decade civil war opened in early 2006, and the announcement came hours after suspected Tiger rebels bombed a military bus in downtown Colombo, killing four and wounding 24.
An army soldier stands guard at a road side checkpoint in Colombo.
The move would allow for a governement military campaign to recapture the rebels' de facto state in the north of the island
The Liberation Tigers of Tamil Eelam are fighting for an independent state in north and east Sri Lanka.
More than 5,000 people have been killed since early 2006, taking the death toll since the war began in 1983 to around 70,000.
Violence continued today. The military said it destroyed six rebel bunkers in the northwestern district of Mannar, killing six Tigers, while the pro-rebel website, www.tamilnet.com, said the insurgents had thwarted a major army offensive and killed 10 soldiers in apparently the same incident.
Separately, two soldiers were killed in a mine blast in the northern district of Polonnaruwa.
Norway, which brokered the 2002 truce, said a Nordic mission monitoring the ceasefire would now most likely be withdrawn.
Norway Development Aid Minister Erik Solheim said he feared the Sri Lankan government's decision to end the ceasefire, which he called a "negative and sad development", would lead to an escalation of violence.