A Russian businessman who spent five years in an Israeli jail on charges of spying for the KGB has been shot dead in Moscow. Sixty-year-old Shabattai Kalmanovich was gunned down near his apartment in central Moscow on Monday.

File photo of shot dead Shabattai Kalmanovich(R), the chief executive of Spartak's women's basketball team. Kalmanovich, 60, a Russian businessman convicted in Israel in the 1980s of being a KGB spy, was gunned down Monday near his apartment in central Moscow after unidentified gunmen opened fire on his Mercedes from a passing car, Moscow city police said.[Xinhua/AFP File Photo]

Moscow city police said unidentified gunmen shot at Kalmanovich's Mercedes from a passing car, firing at least 20 rounds. The head of the Moscow Investigative Committee Anatoly Bagmet said the killing appeared to have been "carefully planned," and could have been motivated by "personal revenge." Investigators are looking for at least two assassins. Kalmanovich was born in Soviet Lithuania and emigrated to Israel in 1971.

He reportedly agreed to spy for the KGB in return for a permit allowing him to leave the Soviet Union. During the 1970s and 1980s, he was a close Israeli government insider, and passed along state secrets for 17 years until his arrest and conviction in 1988.

Following his release, he moved to Sierra Leone, where he made a fortune in the diamond trade. Since 1994, he was the director general of the large Tishinsky shopping center in Moscow.