A top Sri Lankan military intelligence officer responsible for operations against Tamil rebels has been shot dead by an unidentified gunman, police said yesterday.

Commanding officer of the Intelligence Unit Major Nizam Muthalif, 39, was killed at Narahenpita in the capital yesterday while on his way to a military academy in the outskirts.

"A motorcycle without its registration number blocked the path of the officer's vehicle and the pillion rider got off the bike and sprayed the car with bullets, before escaping," a witness to the incident said.

The driver of the vehicle had seen the bike and told Major Muthalif that he was in danger, prompting the officer to try to get down from the vehicle with his service weapon.

But he was not able to fire as the assassin sprayed him with bullets, police said. "There is no trace of the motorcycle or the persons who killed him," a police officer involved in the investigations said.

Major Muthalif was rushed to the nearby Apollo hospital but was pronounced dead at the hospital.

In view of the threats to his life the army had provided him with additional bodyguards, but he had left home without them, police said.

Muthalif had been transferred to the commanding post in the Sri Lankan Military Intelligence a few years back after a successful stint in the northern Vavuniya District.

Army officers described him as one of the most important intelligence officers who was able to gather information about the build up of rebels in the capital during the ongoing ceasefire.

Muthalif was also the highest-ranking Sri Lankan Military Intelligence officer to be killed since the Cease Fire Agreement (CFA) was signed between the government and the Liberation Tigers of Tamil Eealm (LTTE) in February 2002 . The LTTE is a party to the Norwegian-backed truce, but it has been involved in killing its rivals and military informants in Colombo and the north and eastern parts of the country.

Over the past three weeks, more than 15 rival members of the LTTE have been killed.

The officer leaves behind his wife Kusum, who also an army officer, and two children.