Sri Lanka's air force has launched more attacks on Tamil Tiger rebel positions in retaliation for a deadly bus attack on Thursday.
Fears are growing of a return to full-scale civil war
Bombs were dropped near a suspected rebel airstrip in Kilinochchi where Tiger headquarters are based on Friday morning and evening.
The mine attack on the bus killed at least 64 people, many of them children.
The air force launched a first wave of raids on rebel positions on Thursday. The rebels deny attacking the bus.
The BBC's Dumeetha Luthra in Kilinochchi says there is fear of a full-scale escalation in the violence.
The Tamil Tigers have warned that a direct attack on the town itself would be seen as a "declaration of war".
Meanwhile, a mass funeral took place on Friday for victims of the bus blast in Anuradhapura district.
Grieving relatives and villagers all gathered to mourn the dead. The coffins of 11 children were laid out in a row.
Friday morning's air strikes by fighter jets on the outskirts of Kilinochchi started just after dawn and lasted about half an hour.
Aid workers and journalists were forced to take shelter in bunkers.
Sri Lankan forces said they had also shelled rebel positions in the Mullaitivu area, in the east of the island, for a second day.
The TamilNet website reported that some of the bombs had dropped near a tsunami refugee camp to the south of the town of Trincomalee.
"At least six bombs were dropped near the refugee camp. Two of the bombs did not explode," it said.
A second raid took place in the evening. There have been no reports of casualties.
On Thursday, government spokesman Keheliya Rambukwella said the administration would have to "seriously consider" the ceasefire agreement signed in 2002.
Many children died in Thursday's bus bombing
The bus attack in Anuradhapura - an area with an ethnic Sinhalese majority near rebel territory - was the worst involving civilians since the truce was signed.
The killings brought a tide of international condemnation.
"This attack is much more than a ceasefire violation," UN High Commissioner for Human Rights Louise Arbour said.
She said those behind the attack should face not only justice, "but the full censure of the international community".
The Tigers denied involvement in the bus attack, saying the bombing might have been the work of a paramilitary group linked to the government.
President Mahinda Rajapakse visited victims of the bus attack and said he remained committed to peace.
But suspected attacks by Tamil Tigers on security forces and killings of Tamils blamed on the army and others have soared in recent months.
Earlier this month the rebels refused to meet the Sri Lankan government side in talks in Oslo, mediated by Norway.
The Tamil Tigers want a separate homeland for minority Tamils in the north and east of Sri Lanka. More than 60,000 people have died in two decades of conflict.