Amnesty International says hundreds of people have been abducted in eastern Ukraine during the past three months -- mostly by pro-Russian separatists -- and most of the victims are being tortured.
Denis Krivosheev, Amnesty International’s deputy director of Europe and Central Asia, said on July 11 that "the bulk of the abductions are being perpetrated by armed separatists, with the victims often subjected to stomach-turning beatings and torture."
"There is also evidence of a smaller number of abuses by pro-Kyiv forces," he added.
The international rights group says there are no comprehensive or reliable figures on the number of abductions, but the Ukrainian Interior Ministry has reported nearly 500 cases between April and June 2014.
It notes that the UN Human Rights Monitoring Mission for Ukraine has recorded 222 cases of abduction in the last three months.
Amnesty International also says its own research team has met with various ad hoc self-help groups that have been collating details on the escalating number of abductions.
The research team was provided with a list of more than 100 civilians who have been held captive, with allegations of torture in the majority of cases.
One pro-Kyiv activist, who gave his name as Sasha, described to Amnesty researchers how he was tortured.
The 19-year-old said he was beaten and then "after half an hour, 40 minutes you don't feel the pain. So they started to electrocute me. They even took cigarettes. They stubbed out cigarettes on my leg and then stubbed another cigarette in the hole in my leg."
Krivosheev told RFE/RL that "the evidence of what's going on is mounting up very fast and we can suddenly speak about a considerable number of cases, probably hundreds of cases of people abducted, unlawfully detained and ill treated and tortured in the east of Ukraine."
But he said compiling a full picture of the number of cases was complicated by the reluctance of some victims to come forward.
"Many people [who have gone through abduction and torture] I should stress, are not ready to [share their testimonies] publicly because they still have families back in the east and they feel that by going public they would be exposing their relatives’ safety," he said.
Amnesty International says the abductions have taken place across eastern Ukraine, principally in the Donetsk and Luhansk regions, and that those targeted include not only police, the military and local officials, but also journalists, politicians, activists, members of electoral commissions, and businesspeople.
The rights group says that while most abductions appear to have a “political” motivation, there is clear evidence that abduction and torture is being used by armed groups to exert fear and control over local populations.
People have also been abducted for ransom.
Amnesty International is calling on the Ukrainian government to create a single and regularly updated register on reported abductions, and to thoroughly and impartially investigate every allegation of abusive use of force, ill-treatment, and torture.