GENEVA - Up to 50,000 civilians trapped on a tiny strip in northern Sri Lanka are enduring dire hardship, suffering from a lack of food, water and medical care, the International Committee of the Red Cross said on Tuesday.

Hundreds of civilians have been killed or injured in the past 48 hours and more than 1,000 wounded people needing urgent treatment will be evacuated by boat from Wednesday, it said.

I honestly cannot recall a situation as painful and extreme as the one affecting civilians in the Vanni currently, Pierre Kraehenbuehl, director of ICRC's operations worldwide since 2002, told a news briefing in Geneva.

Obviously if a family in Gaza, Darfur or Afghanistan loses close relatives, it is just as painful on a personal level, but it is the intensity and the sense of there being practically no escape for people that makes it so different and even more acute than what I have seen, he told Reuters.

The situation was nothing short of catastrophic in the Vanni, where up to 50,000 civilians are trapped alongside the Liberation Tigers of Tamil Eelam (LTTE) rebels surrounded by government forces in a shrinking strip of just 12 square km (5 square miles).

SHOWDOWN

These civilians face extreme insecurity related to the final military showdown that is taking place in this area, Kraehenbuehl said.

Many had been stopped from leaving the area by the rebels, while the government had prevented vital relief supplies including blood bags from reaching conflict victims, he said.

All the basic needs of these civilians are at present unmet

-- at the level of water, hygiene, food and medical attention. The fear of epidemics, malnutrition and increased deaths due to lack of treatment is growing by the day, he said.

Sri Lanka's social services and social welfare minister, Douglas Devananda, speaking to a U.N. conference on racism on Monday, said that the rebels were using innocent civilians as human shields.

If the international community can pressurise the LTTE to surrender or at least to release the rest of these civilians unconditionally, that will go a long way in ending the suffering of the Tamil minority, Devananda, the senior ethnic Tamil cabinet minister, told the Geneva forum.

Sri Lankan soldiers battled into the last redoubt of the Tamil Tigers on Tuesday and the number of people in an exodus of people from the area reached 62,000, the military said.

The ICRC said that it could confirm at least 13,000 had fled in the last 48 hours. Noting the far higher government figure of displaced, it expected more uprooted people to be on the way.

The ICRC was also keeping close tabs on the fate of people crossing into government-controlled territory, as they also required protection and assistance, Kraehenbuehl said.

There are risks -- and that is what we are monitoring -- of enforced disappearances, of arrests and of killings, which explains the ICRC presence at clearance points, he said.

Access to transit camps as well as hospitals and medical facilities where the displaced are kept was essential to provide independent assistance and protection to such people, he added.

Our assessment is the system is overwhelmed by the influx and is not able to manage adequately despite efforts ... The gap between those requiring medical assistance and care and what is actually provided to them is deep and wide, said Jacques de Maio, ICRC head of operations for South Asia.

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