Major Carlos Eduardo Martiz said the two manuals were found in late 2001 or earlier this year after raids in a southern FARC safe haven. He said the manuals contained information on high-grade explosives and pipe bombs. Such bombs were first used in Northern Ireland before they were used in Colombia, he added.
Maj Martiz also said that leading members of FARC had travelled to Europe for training and that relatives of one leading commander had also travelled to Europe to collect similar information.
Niall Connolly, Martin McCauley and James Monaghan, face 28 years in prison if convicted.
On the first day of evidence in the trial, Judge Jairo Acosta refused to hold evidence by two former IRA members until the prosecution evidence had been heard.
Defence lawyers argued that former IRA hunger striker Laurence McKeown and leading Sinn Féin member Danny Morrison should give evidence after the prosecution. Judge Acosta said that move the sequence for testimony had already been set. He said that he would hear evidence from the pair before he heard prosecution evidence.
A defence lawyer had objected to the line-up and said that while the three accused would not be attending court, they demanded that the prosecution first outline its case before evidence could be heard by the defence witnesses, which includes testimony by Sheila McGuire, an official from the Irish embassy in Mexico who will say that she was with one of the three men in Cuba on one of the dates he was alleged to be in Colombia aiding FARC rebels. The judge said that he would also hear evidence from Ms Maguire before prosecution evidence had been heard.
The three accused have been detained in Bogota's La Modelo jail since August 11, 2001, when they were arrested in a FARC-controlled area of Colombia. The men were found to have false passports and to be travelling under false names. Their lawyer will claim that the men were visiting FARC areas to exchange ideas on peace talks between the government and rebels.
There was tight security around the courtroom as anti-FARC protestors tried to shout down Caitriona Ruane from the 'Bring Them Home' campaign, which is calling for the release of the trio.
"They are the delinquents that bring arms to Colombia and because of that the war continues," said protester Steven Velasquez, 17.
Among those attending the trial include Guildford Four member Paul Hill and a delegation from the Dáil and Seanad.
Colombia's 38-year-old civil war pits Marxist rebels, right-wing paramilitaries and government troops against one another, leaving about 3,500 people dead each year.