A human rights group said riot police in Dagestan beat and detained several people who were protesting abductions and other alleged abuses Wednesday in the volatile Russian province.
Police said several men were detained after what they described as a clash.
Dagestan borders war-scarred Chechnya and is plagued by violence stemming from power struggles, clan and ethnic discord, and growing tension between authorities and civilians they view as Islamic militants or sympathizers.
The prominent rights group Memorial said more than 100 people gathered in a central square in the provincial capital, Makhachkala, to urge the authorities to find and release abductees and end what they is widespread persecution by law enforcement authorities of their perceived foes.
Across Russia's troubled North Caucasus region, relatives of young men who go missing often blame government security forces, while authorities claim that men reported abducted in many cases have actually joined insurgent groups fighting against the government.
Some of Wednesday's protesters were relatives of five men reported abducted recently, two of whom said they escaped and described a harrowing ordeal at the hands of their captors.
In a statement, Memorial said some of the protesters shook a fence separating the provincial government headquarters from the square. It said riot police arrived after a scuffle between city police and women in Muslim head scarves, and that about 15 of the women in traditional Muslim dress were detained. It said the riot police beat young men in the crowd and detained several of them, as well.
A top Makhachkala police official, Shamil Guseinov, said police intervened after some of the protesters tried to get into the government building and that police and protesters clashed shortly afterward in a nearby park. He said several male protesters were detained.
The protest came after what Memorial said were the abductions of three men Sunday, including two brothers it said were seized by assailants who placed sacks over their heads and took them to a building where they were beaten and tortured in an effort to extract statements from them saying they were members of militant groups.
According to Memorial, assailants later bound the three men's hands with tape and put them in a car along with two men abducted earlier, then poured gasoline on it and placed an explosive device in the driver's seat. It said two of the men escaped — tossing the explosive device out of the car, where it exploded — but that the other three remained missing.
Law enforcement officials could not immediately be reached for comment on Memorial's claims.