Sri Lankan forces fought their way on Wednesday into another village still held by Tamil Tiger rebels, an official said, as neighbouring India raised fears for civilians caught up in the war.
Soldiers marched into the village of Visuamadu in the final phase of operations against the Liberation Tigers of Tamil Eelam (LTTE), a military official said, with helicopter gunships also deployed in the concerted push.
The guerrillas had pulled back their long-range artillery guns into an area declared a "safe zone" for civilians and were firing at the military from there, the defence ministry said.
The Tigers wanted to create a "last-minute civilian tragedy" because the army was about to completely defeat them, the ministry said in a statement.
More than 250 civilians have been killed and over 1,000 injured since the beginning of January, said T. Varatharajah, Regional Director of Health Services for the battle-scarred northern district of Mullaittivu.
"There are dozens of unclaimed bodies lying in the hospital mortuaries because no relatives are coming forward to claim them," Varatharajah told AFP by telephone.
The pro-rebel Tamilnet.com website says the civilian toll is far higher.
Sri Lanka has dismissed charges of widespread civilian deaths with military spokesman Brigadier Udaya Nanayakkara branding such claims part of a "cheap propaganda exercise" by the Tigers.
But Indian Foreign Minister Pranab Mukherjee, on a surprise visit to Sri Lanka, called for urgent measures to protect civilians caught up in the island's ongoing fighting.
Mukherjee held talks with President Mahinda Rajapakse and left on Wednesday after getting assurances of safety for Tamil civilians.
Sri Lanka's minority ethnic Tamils have close cultural and religious links with the 55 million-strong Tamil population in the south Indian state of Tamil Nadu.
The territory under the control of the Tigers has been rapidly shrinking since mid-2007 and the guerrillas lost their last urban centre when the military seized the town of Mullaittivu on Sunday.
Government forces are battling to capture 30 kilometres (18 miles) of seafront north of Mullaittivu.
Seizing the coastline would leave the remaining LTTE forces -- and possibly Tamil Tiger leader Velupillai Prabhakaran -- encircled by ground troops.
The fighting came as the International Committee of the Red Cross (ICRC) sounded the alarm over what it said was a major humanitarian crisis in northern Sri Lanka, where 250,000 ethnic Tamil civilians have been caught up in the war.
Medical facilities there were overwhelmed by "hundreds of dead and scores of wounded," the ICRC said in a statement from its Geneva headquarters.
"It's high time to take decisive action and stop further bloodshed because time is running out," said Jacques de Maio, ICRC head of operations for South Asia.
During clashes Tuesday, security forces engaged the rebels in five different areas in the small triangle of coastal territory still held by the LTTE and killed 19 rebels, the military official said.
He did not say whether government troops suffered any losses.
The Tigers, meanwhile, have prevented international aid workers from evacuating nearly 400 hospital patients inside rebel-held territory, a doctor in the area said.
A two-dozen vehicle convoy arranged by the ICRC and the United Nations to transport the sick was barred from crossing the frontline, the doctor said.
However, the UN said Wednesday that it will revive an attempt to evacuate "hundreds of critically wounded" people, including 50 children, from the Puthukkudiriruppu area, in the island's embattled north, on Thursday.
Tens of thousands of people have been killed since the Tigers launched their war for a separate Tamil homeland in 1972. The Colombo government stepped up its assault on the rebels after pulling out of a ceasefire last year.