At least five people have been killed and 30 injured after a bomb attack on a bus in Sri Lanka, officials say.
The blast occurred near Nittambuwa town, 40km (25 miles) north-east of the capital Colombo.
There were about 80 civilians on board at the time of the attack, which took place during the evening rush-hour.
Defence ministry officials have blamed suspected Tamil Tiger rebels for the attack. However, the Tamil Tigers have denied any involvement.
Sri Lankan army spokesperson Brigadier Prasad Samarasinghe told the BBC Tamil Service that a bomb had been placed under a seat on the private bus.
The Tigers have denied carrying out the attack, saying they condemn the killing of innocent civilians.
Earlier, the Sri Lankan military said it had bombed Tamil Tiger rebel positions in the north of the country for the fourth day in a row.
A military spokesman said the early morning raids destroyed a rebel naval base in Mullaittivu district.
At least 16 civilians were killed in an airstrike in the north-west on Tuesday - the rebels and others said government planes had attacked a fishing village.
The government has admitted some civilians might have been killed in the attack, but said they were being used as human shields.
Meanwhile, in the east of the country, the government is trying to capture some areas now under Tamil Tiger control.
The BBC's Roland Buerk in Colombo says both sides are supposed to be observing a ceasefire, but the agreement has been left in tatters by fighting in which more than 3,500 people were killed last year.