Complaints of torture in Russia’s penal system have doubled over the past year, the country’s top human rights official has said.

Russian law enforcement has been rocked by several torture scandals in recent years, with reported victims including LGBT people in Chechnya, Jehovah’s Witnesses and prisoners. Recent polling has said that one in 10 Russians have been subjected to what they perceived to be torture by law enforcement officials.

Tatyana Moskalkova, Russia’s human rights ombudswoman, did not specify how many Russians filed complaints with her office when mentioning that their number had doubled, Interfax reported.

Russia has paid out 770 million rubles ($12 million) in the past year to its own nationals in cases filed in Europe’s human rights court, Moskalkova told the State Duma’s Social and Religious Organizations Committee.

Most of the European Human Rights Court (ECHR) cases dealt with refusals to open criminal cases, prolonged investigations and lengthy prison terms, she added.

UN human rights investigators last year called on Russia to halt the frequent torture of detainees and to prosecute perpetrators.