A former loyalist prisoner has secured a last-minute court order to stop police collecting interviews he gave to a US university project.
PSNI detectives investigating murder and other paramilitary crimes travelled to Boston today after a judge threw out Winston "Winkie" Rea's bid to halt any handover.
But with their flight mid-Atlantic Rea's lawyers went into the court of appeal to seek an emergency restraining order.
Following legal arguments a panel of three judges banned police from taking possession of the recordings until at least Friday.
Rea will then attempt to renew an argument that the PSNI move breaches his right to privacy.
He was among dozens of loyalists and republicans who provided testimonies to Boston College researchers compiling an oral history of the Northern Ireland conflict.
Interviews were given on the understanding that tapes would not be made public until after their deaths.
But those assurances were dealt a blow in 2013 when detectives investigating the abduction and murder of Belfast mother-of-ten Jean McConville back in 1972 secured the transcripts of former IRA woman Dolours Price's account.
That material was handed over following court battles on both sides of the Atlantic.
Rea, a son-in-law of the late UVF leader Gusty Spence, claimed a subpoena for his tapes is unlawful and unspecific.
But during judicial review proceedings the court was told an investigation has been launched into serious crimes stretching from the seventies to the late nineties.
The alleged offences include murder, directing terrorism, membership of a proscribed organisation and robbery.
An international request for the tapes said police have information that Rea was a member of the Red Hand Commando whose interviews would assist investigations into those crimes.
It claimed he has "a long involvement in organising and participating in terrorist offences in Northern Ireland, including murder, directing terrorism and robbery".
He was also alleged to have acted as a personal security guard to Spence and met with former British Prime Minister John Major in 1996 - a claim disputed by Rea.
Yesterday Mr Justice Treacy threw out his challenge after holding that the test for seeking the material had been met.
He said it was "manifest" from the terms of the request that a police investigation was under way.
"The request was plainly lawful," the judge said.
"There is no credible contention that the applicant's rights (under the European Convention on Human Rights) are infringed."
His ruling appeared to clear the way for detectives to fly to America to take possession of recordings of the loyalist's interviews.
But those plans have been put on temporary hold again following tonight's court of appeal order.