The officers raided an apartment before dawn, taking away the owner, well-known opposition figure Vasilia Innoyatova, and 27 others.

The group had been planning to hold a small rally to protest about the killings in Andijan two weeks ago.

Hundreds reportedly died when troops fired on an anti-government protest.

The government says those who died were members of an extremist Islamist group, and is taking a hard line against anyone challenging this version.

President Islam Karimov refused to meet a group of US senators who came to Tashkent on Sunday to push for an international inquiry.

They did meet Mrs Innoyatova just hours before she was detained.

In Andijan itself, most residents are still too frightened to talk openly, but some say, quietly, that the security forces are making night raids on the houses of anyone who might have been among the crowd, or other witnesses.

One family told us that militia in riot masks burst their door and took away their son for interrogation.

Others report that their sons have been arrested while searching at a hospital for relatives still missing two weeks on.

The atmosphere generally in Uzbekistan is still one of shock and fear about what happened in Andijan, and worry about what the future may hold.