MOSCOW, September 29. /TASS/. Group-IB founder Ilya Sachkov, arrested earlier over charges of treason, worked for foreign intelligence and handed them classified information on cybersecurity, according to the investigation, a source in law enforcement told TASS.

"The investigation suspects Sachkov of handing over classified information on cybersecurity to foreign intelligence agencies," the source said.

According to the source, Sachkov could have been "employed" by intelligence agencies of several countries, but they will not be named in the interest of the investigation.

"The Federal Security Service (FSB) military counter-intelligence has joined the investigation," the source said.

Earlier, the media reported that searches happened in Group-IB offices. The company’s press service said it is unaware of the reasons for the investigative measures.

A court arrested Sachkov until November 27. He denies the charges of high treason inflicting reputational and national damage to Russia’s interests. He also denies that he collaborated with foreign intelligence services, a TASS source said.

The case materials are classified and no further details are available.

In 2016, Sachkov was included in the Forbes 30 Under 30 list. He is an associate professor of the Bauman Moscow State Technical University IT Security Department, and a member of Russian State Duma and Foreign Ministry expert committee.