A Sri Lankan military helicopter releases flares as it flies over a naval base in Trincomalee. (AFP)

Jaffna, Aug. 12 (Reuters): Sri Lanka’s Tamil Tiger rebels broke through military defences in the island’s far north and overran army bunkers today, truce monitors said.

The Tigers and army exchanged intense artillery fire and government jets bombed near the rebels’ forward defence lines in the northern Jaffna peninsula, residents said, as thousands of civilians fled to churches.

The military said 27 of its personnel were killed and 80 wounded, and estimated it had killed more than 150 LTTE rebels. It said it sank five Sea Tiger boats as they attacked army posts on the shore in Jaffna. “The LTTE is definitely pushing the country to war,” defence spokesman Keheliya Rambukwella said.

Analysts said they suspected the Tigers were trying to divert pressure from their fighters battling in the east and disrupt military supply lines to the north.

The unarmed Nordic Sri Lanka Monitoring Mission said the Tigers had overrun five bunkers inside army lines, and had landed troops on an island west of Jaffna and engaged the navy.

About 40,000 troops are stationed in Jaffna, which is cut off from the rest of the island by rebel territory.

“What we are seeing now I am interpreting as an attempt to cut off the line of the security forces in Jaffna,” said chief truce monitor Major-General Ulf Henricsson. “The ceasefire agreement is definitely not on just now in these areas. There is no respect at all, they just don’t care about it — both parties.”

As civilians from coastal villages sought refuge, foreigners headed to a UN compound after being warned to leave immediately.

Sporadic violence flared in the capital again today, when suspected Tigers shot and killed the deputy head of the government peace secretariat, Kethesh Loganathan.

Sri Lanka’s main donors — the US, the EU, Japan, and Norway — have lost their patience.

“The co-chairs call on the government of Sri Lanka and the LTTE to cease hostilities immediately and return to the negotiation table,” they said. “The suffering inflicted on innocent civilians is intolerable.”

In the east of the island, the Tigers rained artillery on the strategic port of Trincomalee, a vital maritime army supply line to Jaffna. The military said there was some damage, but gave no details.

A Reuters witness in Jaffna, where the army has declared an indefinite curfew to keep people in their homes, heard fierce artillery fire to the east.

Electricity was cut off for hours. Sri Lanka’s Tamils consider Jaffna their cultural homeland, and analysts say the Tigers are intent on recapturing it. Some distraught residents dread being displaced yet again.

“We cannot go on like this forever,” said Richard, a retired Tamil merchant seaman, who declined to give his full name. “It is better to hand over Jaffna to the LTTE. Only then will this stop. Until then, this war will go on.”