Russia has reportedly been taking DNA samples from religiously conservative Muslim women in the North Caucasus as part of its security measures for the 2014 Winter Olympics in Sochi.
The DNA would be used to identify body parts should any of the women carry out suicide bomb attacks on Olympic targets.
Eight Dagestani women contacted by the Reuters news agency said they had been asked to provide swabs of saliva.
Locals said the DNA tests were part of a sweep after a suicide bombing in the capital Makhachkala in May.
The move coincides with a crackdown by President Vladimir Putin on an Islamist insurgency in Dagestan, which lies east of the Sochi Games sites.
Critics say the new hard line being taken by Mr Putin is feeding the resentment that lies behind insurgent attacks in the region.
In July, Doku Umarov, the leader of the Islamist insurgency, urged his fighters to use “maximum force” to sabotage the Sochi Olympics.
A suicide bombing on October 21 that killed six people in Volgograd, a major city north of Sochi, was blamed on a woman from Dagestan.
Dubbed “black widows”, some 49 female suicide bombers have carried out attacks in Russia in the past 13 years, according to the Caucasian Knot website.
In response, security forces have blown up the homes of militants’ relatives, sealed off mountain villages and rounded up young men suspected of having ties to militants: see more