They also disclosed that although pounds 766,000 had been spent on interviewing witnesses in at least 10 countries, the subject of the inquiries was never approached.
Mr Gecas's term as an officer in a unit used by the Germans as a killing squad was revealed publicly in 1986, after his name was given to the Home Office by the Los Angeles-based Simon Wiesenthal Centre, which has brought scores of Nazi war criminals to justice.
Mr Gecas, 77, served in a Lithuanian battalion, set up by the occupying Germans, which murdered thousands of civilians in Eastern Europe. He came to Britain in 1946 posing as a Pole after he and 80 fellow soldiers had joined a Polish regiment and, having laundered their past, were allowed into Britain as refugees.
Since the passage of the War Crimes Act in 1991, a unit attached to Strathclyde Police has been working to compile a case against Mr Gecas. The strength of evidence against him by 1989 was vital in persuading the successive Home Secretaries, Douglas Hurd and Kenneth Baker, to force the Act through Parliament, to allow foreign nationals who later became British citizens to be prosecuted for murders committed on foreign soil.
The all-party Parliamentary War Crimes Group was surprised by the announcement yesterday that the police unit was being disbanded. Its chairman, Lord Merlyn-Rees, a former Labour Home Secretary, said: 'We note the allegation of links with British intelligence and we can only express the hope that this has not been a factor in the decision.'
It is known that MI6 used former refugees from Eastern Europe for intelligence gathering in the late Forties and Fifties, but the Independent has no evidence that Mr Gecas was involved. The group had also heard suggestions that 'important interviews' had not been undertaken. 'We hope these allegations will be examined quickly,' he said. They are to raise the issues in Parliament.
The Crown Office in Edinburgh refused to discuss its inquiry yesterday, or to expand on a short statement saying: 'After careful consideration, Crown Counsel have decided that as matters stand there is not at present sufficient evidence for a criminal prosecution in any of the cases reported to them.' The Scottish unit would be disbanded, but the inquiry could be reopened for fresh evidence, it said.
Mr Gecas's lawyers in Edinburgh said they had 'no comment' on the announcement. Mr Gecas was not answering the front door of his home yesterday.
Mr Gecas has publicly admitted that he joined a Lithuanian police battalion, went with the Germans to Byelorussia and later wore German uniform and fought in Italy. But he said that if Jews were rounded up and killed, he had no knowledge of it.Reuse content