Waging a desperate battle for survival, the Tamil Tigers launched a wave of suicide attacks on land and sea, but failed to stall the advance of Sri Lankan forces, who broke through their defences as fierce fighting left 44 rebels dead and many soldiers wounded.

The renewed heavy fighting raged as both sides ignored new international calls for ceasefire. Aid and rights groups claimed that the civilians were being used as "cannon fodder".

Two divisions of Lankan forces advancing on the trapped LTTE fighters captured a vital causeway, which could help them in organising another break out attempt for an estimated 50,000 people still trapped in the battle zone.

Carrying out "search and clear operations", security forces recovered bodies of 43 LTTE fighters and a huge cache of arms and ammunition in Kariyamullavaikkal, the army said.

Army beat back a ferocious sea-borne suicide attack by Sea Tigers in which three fast moving boats attempted to hit troop positions on the shore.

"Several soldiers were wounded in the attack carried out late last night. Our Naval boats and shore-based guns foiled the attack forcing the Sea Tigers into their own area," a military spokesman said.

The army had confronted similar suicide attacks by land-based Black Tigers who blew themselves up  in front of the advancing Lankan columns. Ten bombers were killed in these attacks.