Army officers help an injured baby near the war zone in northeastern Sri Lanka. (AP)

Colombo, April 22 (AP): Two senior Tamil Tiger leaders surrendered to the Sri Lankan army today, and refugees joined a stream of more than 80,000 people the government says have fled a war zone that appeared to shrink by the hour.

The sandy beaches north of the tiny combat zone — which now measures just 8km long — were filled with people carrying their belongings on their backs or in bundles on their heads, according to photos released by the military. Mothers held infants and others carried sick relatives as they reached government territory in boats escorted by the navy.

In a sign that the rebel leadership has begun to feel the military pressure, the rebels’ former media spokesman Velayutham Dayanithi, whose nom de guerre is Daya Master, and an interpreter for the group’s political wing, known only as George, turned themselves over to government forces today. The two played prominent roles in talking to the media and visiting foreign diplomats in a now defunct peace process.

The former spokesman is the most senior rebel official to surrender so far, military spokesman Brigadier Udaya Nanayakkara said. The remaining rebels were still resisting the army’s advance, he said. There were casualties among government troops, but Nanayakkara did not provide details.

The UN and humanitarian groups called for an immediate stop to the fighting, so more civilians could escape. Over the past three days, the military says more than 80,000 have fled after forces broke through a key rebel embankment protecting their territory.

The government has ignored calls to stop the fighting, saying for weeks it was on the verge of crushing the rebels as troops ousted them from their former strongholds and hemmed them into a tiny strip of coastal land. The government had previously deemed that area a no-fire zone to protect civilians. But troops broke through the embankment, entered the zone and captured part of it during fighting Monday and yesterday.

At least 43 rebels were killed, Nanayakkara said. The UN estimates that more than 4,500 civilians have been killed in the past three months.

Yesterday, the rebels accused the government of killing 1,000 civilians in their latest offensive — a charge the military denies.

In the past, humanitarian groups have said troops shelled the densely populated area. Dr Thangamuttu Sathyamurthi, one of the few doctors working in the war zone, said the bodies of 80 civilians were brought to two makeshift hospitals soon after Monday’s raid but said more people would have died and been buried on the spot.

“I think more people would have been killed, we saw only 80 bodies but people have seen a lot more people dead on the roads,” he said, adding that one of his fellow doctors was also among the dead.

Fighting continued today and shells fell near a Roman Catholic church wounding a priest and killing three civilians who had pitched their tents in the church compound, Sathyamurthi said.

The military denies targeting the civilians or using heavy weapons at populated areas. “We suffered casualties because we are not using heavy and long-range weapons. We only use small weapons,” Nanayakkara said, accusing the rebels of firing artillery shells.

It is not possible to confirm accounts from the war zone because independent journalists are barred from entering it. Human rights groups accuse the rebels of holding civilians against their will and using them as human shields, and accuse the government of indiscriminate shelling in the region.