MOSCOW (AP) — The United States on Monday slapped the regional strongman leader of Russia's republic of Chechnya with sanctions over human rights violations.

Ramzan Kadyrov, 43, has run Chechnya like his personal fiefdom, relying on his security forces to quash dissent. International human rights groups have accused Kadyrov and his lieutenants of abductions, torture and killings of their opponents.

Rights defenders also hold the Chechen authorities responsible for a sweeping crackdown on gays over the past few years that has seen more than 100 people arrested, subjected to torture, with some of them killed. Chechen authorities have denied those accusations, and federal authorities said a probe found nothing to support the charges.

In a statement announcing the sanctions, U.S. Secretary of State Mike Pompeo pointed at “extensive credible information that Kadyrov is responsible for numerous gross violations of human rights dating back more than a decade, including torture and extrajudicial killings.”

Pompeo said the restrictions will apply to Kadyrov’s wife and two daughters and he encouraged U.S. allies to take similar measures.

The Kremlin has relied on Kadyrov to stabilize Chechnya after two separatist wars, providing generous federal subsidies and dismissing international criticism of his rule.

The Kremlin also has stood by Kadyrov amid Russian opposition claims of his involvement in the 2015 killing of prominent Kremlin critic Boris Nemtsov, which the Chechen leader has rejected. An officer in Chechnya’s security forces was convicted of shooting Nemtsov on a bridge adjacent to the Kremlin and received a 20-year prison term.