Nikolai Glushkov, a Russian exile who was close friends with the late oligarch Boris Berezovsky, was found dead in his London home Monday night. His body was discovered by family and friends, and the cause of death is not yet clear. According to a statement from the Metropolitan Police, the department’s Counter Terrorism Unit is “leading the investigation as a precaution because of associations that the man is believed to have had.” So far, there is “no evidence to suggest a link” to the attack on fellow Russian Sergei Skripal in Salisbury, authorities said. Glushkov, 68, was granted political asylum in the U.K. after working for Russian state airline Aeroflot and Berezovsky’s car company. While living in Russia, he was sentenced to five years in jail for money laundering and fraud in 1999, as Berezovsky fell out with Vladimir Putin and fled to the U.K. In 2011, Glushkov also gave evidence to British courts that were ruling on a lawsuit Berezovsky had filed against another Russian oligarch, Roman Abramovich, who has been on good terms with the Kremlin. The judge dismissed Berezovsky’s lawsuit, and Glushkov filed a formal appeal of the case. Berezovsky was found dead in his ex-wife home’s in 2013. Last year, Glushkov was sentenced to eight years in prison by a Russian court in “a trial in absentia” for allegedly stealing $123 million from the car company. This comes as Skripal, a former Russian military intelligence corporal and spy for the British, was attacked by a nerve agent in a mall in South England—triggering reactions from Prime Minister Theresa May, now-former U.S. Secretary of State Rex Tillerson, and U.S. President Donald Trump.