Scenes following the bomb attack
At least 12 policemen have been killed and many more wounded in a suicide bombing in Sri Lanka's northern town of Vavuniya, police say.
A man on a motorcycle reportedly detonated explosives in front of a police office in the town, 250km (120 miles) from the capital Colombo.
The area has been sealed off and the injured have been taken to hospital.
It is not clear who carried out the attack but suspicion has fallen on Tamil Tiger rebels.
The rebels have been blamed for a recent series of bombings in Sri Lanka.
School children were among around 40 victims being treated for their wounds after Monday's attack, hospital officials said.
There has been intense fighting between the rebels and the army in the north of the island over the last month.
The military is carrying out an offensive which it says is aimed at crushing the rebels by the end of this year.
Troops drove the Tamil Tigers from strongholds in the east last year.
Both sides in the war in the north claim to have inflicted heavy casualties on the other in recent weeks.
It is impossible to verify either account because the government bars journalists from the frontline areas.
Tamil Tiger rebels have also been blamed for a spate of recent bomb attacks in and around Colombo, mainly targeting buses and trains.
Dozens have been killed and many more wounded.
The rebels have accused the military of the roadside bombings which have killed many civilians in the rebel-held north. The government has denied the allegations.
Sri Lanka's civil war has intensified since the government formally ended a ceasefire with the rebels in January. In practice, the truce had been dead for months.
The rebels have fought for a generation for an independent state for the Tamil minority in the island's north and east.
About 70,000 people have been killed since the civil war began in 1983.