A MISSING businesswoman alleged to have been murdered may have been an undercover police mole, a trial has been told.

Defence lawyers made the claim at the High Court in Glasgow during the trial of four men accused of murdering Lynda Spence.

Ms Spence, 27, has not been seen since leaving her parents' home in April 2011.

David Parker, 37, from West Kilbride, Paul Smith, 47, from Largs, Philip Wade, 42, from Glengarnock, all North Ayrshire, and Colin Coats, 42, from Glasgow, are on trial accused of abducting, torturing and murdering her.

They deny all the charges against them.

Defence QCs Gary Allan, who is representing Wade, and Derek Ogg QC, representing Coats, suggested that Ms Spence had been recruited by the Scottish Crime and Drug Enforcement Agency (SCDEA) as an "informer", to pass on information about a man named Sokal Zefaj, who they claim is part of an Albanian organised crime gang.

Ms Spence was said to have been married to Mr Zefaj and the lawyers pointed to this as a possible reason for her being recruited by the SCDEA.

Mr Allan asked witness detective sergeant Aileen Boyle, who interviewed Coats for almost five-and-a-half hours, if she had been made aware of such a claim.

Ms Boyle said she had not.

She said no SCDEA officers were present on May 13 2011, when Ms Spence's missing person inquiry became a "major investigation" after the case was deemed "high risk".

Mr Allan said: "We may hear that far from being an ordinary businesswoman, she (Ms Spence) was in fact up to her neck in criminal activity." Ms Boyle replied: "I would agree she was involved in criminal activity."

Mr Ogg said Ms Spence was married to Mr Zefaj, and it was "for this reason that she was recruited by the SCDEA and a UK agency, the Serious Organised Crime Agency".

He asked Ms Boyle: "If this had been known, would it have placed Ms Spence's life in danger?" Ms Boyle relied: "If that were the case, there would be serious concern for her safety."

The lawyer also claimed that a woman who Ms Spence was living with at the time of her disappearance contacted the missing woman's SCDEA "handler" with concerns about her safety two days after she vanished.

Ms Boyle again said she had no information on this.

Parker, Smith, Wade and Coats are alleged to have forced Ms Spence into a car on April 14, 2011 and held her hostage for up to a fortnight. It's alleged they cut off her thumb, crushed her toes and killed her. The trial continues.