The raids lasted at least six weeks and as many as 200 people are believed to have been detained. The number of detainees executed is unclear, but the number could be anywhere between 27 and upwards of 56, Novaya Gazeta reported.

Novaya Gazeta said it had sent its findings to Russian law enforcement officials in April.

Russia’s chief human rights officer Tatyana Moskalkova told the newspaper two people on Novaya Gazeta’s list did not live in Chechnya, and a review of information regarding other alleged victims is continuing but “going much more slowly than it should be.”

The victims are believed to have been brought to secret prisons, where they were held for several weeks, executed, and buried in unidentified graves.

A Novaya Gazeta report in April claimed that dozens of gay men in Chechnya had been held and tortured as part of a massive anti-gay crackdown.

Sunday’s report said the newspaper’s investigation into the killing of two gay men in Chechnya had led them onto the trail of even more extra-judicial killings in the southern republic.

Chechen officials have denied the accusations, even going so far as to call the reports “slanderous.” They suggested that gay people do not exist in the conservative, Muslim-majority North Caucasus republic.