Ciaran Cummings was shot on his way to work

"We are very hopeful of recovering this motorcycle and it is our belief that it hasn't travelled too far.

"But notwithstanding the excellent response we have received, we do urge anyone with information to contact the incident room at RUC Antrim."

He said the police would have to take seriously a claim from the Red Hand Defenders that it carried out the murder.

"We are keeping an open mind as to the veracity of this claim," said Superintendent Meek.

Mr Cummings was approached by two men on a black motorcycle and was shot several times. He died at the scene.

A person claiming to speak for the dissident loyalist group the Red Hand Defenders said it carried out the shooting.

Several loyalist groups, most notably the Loyalist Volunteer Force, have used the title of the Red Hand Defenders as a cover name.

'Full of dreams'

The family's parish priest, Father John Murray, said the Cummings were struggling with their pain.

Fr Murray described the 19-year-old as "full of life, full of dreams and ambitions".

"He was full of life, as we all are at 19 years of age.

"He was hoping to save up and buy a car and hoping to make a life for himself and his girlfriend."

Local nationalist and unionist political representatives have said they believe it was a sectarian murder by loyalists.

Speaking in the House of Commons on Wednesday, Prime Minister Tony Blair condemned the murder, which he said was "a tragic and terrible event".

This young man and his friends had received verbal threats from the LVF

Martin Meehan Sinn Fein

Sinn Fein councillor, Martin Meehan, said the victim had received "verbal threats from the LVF".

Speaking on Wednesday, he said: "His young sister was told a week ago by a well-known loyalist that he would be shot dead along with his friends," he said.

Ken Wilkinson, a local representative from the Progressive Unionist Party, which is linked to the loyalist paramilitary UVF, said Mr Cummings' distraught father visited him shortly after the murder to see if he could find out any information about it.

The police believe that after the shooting the attackers made their way up the Greystone Road in the direction of the M2 motorway and have appealed for information.

SDLP assembly member Donovan McClelland appealed to community representatives to try to calm tensions following the murder.