Shabtai Kalmanovich, 62, a long-term Soviet spy and later a Shin Bet informant, was murdered in Moscow yesterday, in what experts called an act of revenge by business rivals.

Kalmanovich was one of Israel's most colorful Russian immigrants. He was well connected to Israel's political, military and business elite during the 1970s and 1980s, and as a KGB agent, he made concerted efforts to work his way into the centers of power in Israel.

During the latter part of his life, he became a successful international businessman, but became mixed up in fraud.

Moscow police said Kalmanovich was murdered while driving near his home, close to the local police station. Also in the car were his driver, a bodyguard and a friend. The driver was severely wounded.

The shooter may have been in a passing car.

Police sources believe that the murder is linked to Kalmanovich's business activities, and possibly his prominent role in Russian basketball.

Moscow Investigative Committee head Anatoly Bagmet also suggested revenge might have been a motive.

The murder appeared to have been "carefully planned," and investigators are looking for at least two assassins, Bagmet said.

Kalmanovich was born in Lithuania in 1947.

He was an automation engineer by training, but he never worked in the field. After he was drafted into the Soviet army, he was approached by the KGB, which asked him to collect intelligence among Jews seeking to emigrate to Israel. He agreed, and occasionally relayed information about his colleagues and about Jewish activities in Lithuania.

After he was discharged, he and his family were authorized to emigrate to Israel. He immigrated in the 1970s.

In Israel, Kalmanovich continued to spy for the KGB. This made him unusual among Soviet immigrants - many others had accepted similar offers in order to immigrate, but cut contact with their handlers and reported the espionage attempts to the Israeli authorities.