According to the security committee, authorities in Kazakhstan have detained Karim Massimov, the former chairman of the national security committee, on charges of treason.

Massimov was held along with many other officials, according to the National Security Committee, who were sacked this week as protests erupted across the Central Asian country. It didn’t name them or give any other information.

Reuters was unable to reach Massimov right away.

Hundreds of people have died, and public facilities across Kazakhstan have been looted and burned down in the worst violence the former Soviet nation has seen in its 30 years of freedom.

After several days of violence, security forces appeared to have reclaimed the streets of Kazakhstan’s main city by Friday. The Russian-backed president, Kassym-Jomart Tokayev, said he had ordered his troops to shoot to kill to put down a countrywide uprising.

At Tokayev’s invitation, a Russia-led military alliance has been deployed at a time of high tension in East-West relations. Russia and the United States are gearing up for talks next week on the Ukraine crisis.

Massimov is widely viewed as a close ally of former president Nursultan Nazarbayev. He has twice been prime minister and has also served as head of the presidential administration under Nazarbayev.

Nazarbayev, 81, was the longest-serving ruler of an ex-Soviet state until he turned over the presidency to Tokayev in 2019. His family is widely believed to have retained influence in Nur-Sultan, the purpose-built capital that bears his name.