An international human rights watchdog on Thursday praised Kazakhstan's decision not to extradite a prominent dissident to Uzbekistan and urged other Central Asian states to follow suit and resist Uzbek pressure.

Rights groups say Uzbek police and security services have jailed dozens of activists who tried to speak out about the bloodshed in the city of Andizhan, where troops quelled an uprising on May 13.

On July 4, at Uzbekistan's request, Kazakh authorities detained human rights campaigner Lutfullo Shamsudinov, who witnessed the bloody government crackdown.

But on Tuesday the dissident was handed to the United Nations refugee agency (UNHCR), despite Uzbek demands for his extradition on terrorism charges.

"The government of Kazakhstan has done the right thing and other governments in the region should follow suit," Holly Cartner, the Europe and Central Asia executive director of New York-based Human Rights Watch (HRW), said in a statement.

"The pressure from Uzbekistan is very intense right now, and standing up to it requires real political will."

The Uzbek authorities say 187 people were killed in Andizhan, including 94 "terrorists", and accuses human rights activists like Shamsudinov of "spreading information with the aim of provoking panic among the population".

The United Nations said the real casualty figure may be hundreds more than the official count, and witnesses say some 500 people were killed.

Uzbekistan, backed by Russia and China, has resisted strong international criticism of the use of force in Andizhan and repeatedly rejected calls for an independent inquiry.

More than 400 civilians who escaped the bloodshed and fled across the border into Kyrgyzstan are kept in a local refugee camp, but fears persist that they may be handed to stronger neighbour Uzbekistan.