MOSCOW — Human Rights Watch says Russian authorities have rounded up hundreds of migrant workers in Sochi, the host city of the 2014 Winter Olympics, and expelled some of them for alleged violations of migration or employment regulations.

Jane Buchanan, HRW's Europe and Central Asia associate director, said in Thursday's statement that "it's outrageous for the migrant workers who helped to build Sochi's shiny new Olympic venues to be herded into detention and deported."

Buchanan urged the International Olympic Committee to "send a clear message that these sweeps are completely unacceptable for an Olympic host city and that abusive detentions must stop immediately."

HRW said most detainees were released after several hours, but some have been held for more than a week.

Sochi organizers couldn't be reached for comment late Thursday.