A Sri Lanka Tamil party on Friday accused Tamil Tiger rebels of shooting down a civilian plane carrying 55 passengers that has been missing for three days.

"The debris of the aircraft and the bodies are washed ashore in Nachikuda, Iranaitivu and Kalmunai areas (on the west coast)," Suresh Premechandra, general secretary of the Eelam Peoples Liberation Front, said in a statement."It is now clear that the LTTE (Liberation Tigers of Tamil Eelam) shot down this plane because the Tamil civilians and the airline authorities did not heed to the orders of the LTTE."

The Antonov-24, which had four cockpit crew members from Belarus, vanished soon after taking off from the northern Jaffna peninsula on Tuesday.

Local newspapers have said two private airlines flying to Jaffna had received letters from the rebels telling them to halt operations, accusing them of carrying troops.

Sri Lankan navy officials said on Friday their boats had sighted in seas off the northwestern coast three bodies believed to be passengers from the airplane.

They said navy boats scouring the area between Mannar and the islands of Iranaitivu and Palaitivu off the northern Jaffna peninsula also had recovered two life jackets believed to be from a Lionair Antonov-24.

State radio said today that a joint search operation was likely to be mounted by Lionair officials and representatives of the International Committee of the Red Cross.

Naomi Perera, Lionair's manager for marketing and promotions, said in a statement today the airline had sought the help of divers for an underwater search around Iranaitivu.

The plane was reported missing as government troops fought fierce battles with LTTE rebels just south of the Jaffna peninsula in which hundreds of combatants were reported killed.