INVESTIGATORS believe that employees of Libyan Arab Airways in

Frankfurt planted the bomb which destroyed a PanAm Jumbo jet four days

before Christmas, killing 270 people in and around Lockerbie, according

to the American television network CBS News.

In a follow-up to its report on Wednesday night that the Palestinian

terrorist Ahmad Jibril, sponsored by Syria and Libya, was believed to

have built the bomb, CBS said this morning that the sophisticated device

was in a suitcase which did not belong to any passenger aboard PanAm

flight 103.

The CBS version contradicts a Radio Forth report, which said that an

American agent of the Central Intelligence Agency unwittingly had the

bomb in his luggage. Mr David Johnston, of Radio Forth, said last night

police had given him until today to name his sources for his report

which blamed a Palestinian group for the bombing.

He said he was ''completely confident'' he had been told the truth,

and was prepared to face court moves if necessary.

Mr Johnston said he was told by official agencies ''in Britain and

elsewhere'' that the bomb was planted at Helsinki in the luggage of an

American CIA agent returning from an unsuccessful attempt to release US

hostages in Beirut.

Police gave him until today to approach his sources to ask if he could

divulge them, he added.

The officers said that if he did not want to disclose his sources to

them, they would make available ''anyone in Britain, including the Prime

Minister, for him to disclose them to.''

Mr Johnston said the police ''have said that if I don't tell them

tomorrow where the story came from, it would be open to them to put me

before a sheriff under precognition.''

CBS said that at least 100 Libyan airline employees are intelligence

operatives under the command of Abdullah Senoussi, who is related to the

country's leader Colonel Muammar Gaddafi.

Senoussie reportedly has a printing plant which produces forged

luggage tags, among other documents. The bomb, said by CBS to contain

20lbs of plastic explosives, was in a suitcase falsely labelled to fly

to New York, via London, on flight 103. It was not searched, x-rayed, or

even weighed-in at Frankfurt airport, where it was smuggled in through a

''back door,'' the TV report said, citing an American source.

CBS said the device was believed to be identical to a suitcase bomb

found by West German police, in the days before the Lockerbie disaster,

when they arrested 14 members of Jibril's Popular Front for the

Liberation of Palestine -- General Command. The report said the PFLP-GC

wished to upset the peace initiative of the Palestinian leader Yasser

Arafat.

Meanwhile, lawyers representing families bereaved in the Lockerbie

disaster are to pursue their claims for compensation through the

American courts. They will also press for a full accident inquiry to be

held as soon as possible.

The first meeting of the lawyers' steering committee will be held in

Glasgow today but its spokesman, solicitor Mr Michael Hughes, said last

night it was virtually certain any compensation claims would be made to

the American courts.

Lawyers would have less than five months to formulate any right of

remedy claims against the American Government. Any other claims would

have to be made within two years of the date of the disaster, he added.

Seven British lawyers experienced in dealing with the aftermath of

disasters will be at the meeting. Among them will be solicitors who

represented clients bereaved in the Piper Alpha oil rig and Zeebrugge

ferry tragedies.

The lawyers mainly represent relatives of those who died on the ground

at Lockerbie and the small number of non-Americans killed on the plane.

Most of the US victims' families have sought the help of American

attorneys.

Mr Hughes said: ''There is no intention of pursuing any claims in this

country. I can't see anyone objecting to taking such actions to the

American courts.''

* Transport Secretary Paul Channon faced demands last night to check

whether spent uranium posed a radioactive danger aboard the jet. Labour

MP Mildred Gordon tabled a Commons motion claiming spent uranium was

increasingly used as ballast to balance aircraft. Her motion expressed

concern that if a plane loaded with spent uranium caught fire,

radioactive poison could be spread over a wide area.

Firing line