An English war crimes unit in Scotland Yard is believed to have completed three more files detailing strong cases against former East Europeans.
About 90 suspects are being investigated by the specialist unit.
The Independent revealed two weeks ago that more than 30 members of Mr Gecas's own battalion are also alive and in Britain, and have been traced by Scottish police. They are important not only as suspects themselves, but as potential witnesses in any criminal case involving Mr Gecas - they were not available to either side in the civil libel action.
The final decision on whether a prosecution would be in the public interest rests with the Attorney General on the advice of the Director of Public Prosecutions in England, and with the Lord Advocate in Scotland.
In a written judgment at the Court of Session in Edinburgh yesterday, Lord Milligan ruled that Mr Gecas, formerly Gecevicius, was a war criminal, and had therefore lost his libel action against Scottish Television over a documentary made in 1987 detailing his war crimes. There was no jury in the case, by agreement with both parties.
Before yesterday's judgment, there had been a question mark against the credibility of evidence from several elderly witnesses in Lithuania who had changed their stories several times.
But in his 192-page decision, Lord Milligan said he was 'clearly satisfied' that Mr Gecas had 'participated in many operations involving the killing of innocent Soviet citizens including Jews in particular in Byelorussia during the last three months of 1941, and in doing so committed war crimes against Soviet citizens who included old men, women and children'.
Lord Milligan added: 'I further hold it proved that the pursuer (Mr Gecas) was the platoon commander of the 12th Auxiliary Police Service Battalion and that that platoon participated specifically in six operations.
'It inevitably follows that the pursuer committed war crimes against innocent civilians of all ages and both sexes in the course of these specific operations, it not being in dispute that he was in active command of his pla
toon throughout the period mentioned.'
Mr Gecas's lawyers are likely to try to argue that publicity surrounding the libel case has been so great that he could not receive a fair trial before a jury in Britain.
Scottish Television decided to fight the case virtually as a full war crimes trial, although the company knew there was virtually no chance of recouping its costs, estimated at pounds 600,000, because Mr Gecas is practically without assets.
The company first made a TV programme alleging that Britain had taken a decision in 1946 not to prosecute any more war criminals. Then, after the then prime minister, Margaret Thatcher, had said proof was needed that war criminals were at large, the company went to Lithuania to find it. Crimes of War, about Mr Gecas, was made to furnish that proof, and Mr Gecas sued.
Efraim Zuroff, of the Los Angeles-based Simon Wiesenthal Centre, brought the first 17 names of suspects to Britain in 1986, including that of Mr Gecas. He said yesterday: 'This vindicates all our actions. Now there should be criminal prosecutions.'
David Jack, solicitor for Mr Gecas, said his client did not wish to make any public comment on the judgment.
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