GENEVA - MORE than 10,000 Sri Lankan Tamils demonstrated outside the UN's European headquarters in Geneva Monday, accusing the world body of complicity in the 'genocide' of Tamils, police said.

An association for Tamils in Switzerland, the Tamil Forum, released a letter to UN Secretary General Ban Ki-moon condemning what it called the evacuation of civilians from the embattled Vanni region and their placing in 'army detention camps'.

'We are not satisfied with some statements issued by the UN and UN agencies concerning this issue,' the letter published on the Internet said.

The letter criticised calls for an evacuation of civilians, claiming it would force Tamils into the hands of the Sri Lankan army.

It claimed the UN was 'guilty of the culpable complicity in the war of genocide and ethnic cleansing by the Sinhala government'.

The United Nations believes 150,000 to 180,000 civilians remain trapped in the combat zone in northeastern Sri Lanka.

The Geneva-based UN High Commissioner for Human Rights, Navi Pillay, said on Friday she feared both sides could be guilty of war crimes.

There are 'legitimate fears that the loss of life may reach catastrophic levels, if the fighting continues in this way,' she said in a statement. -- AFP