a man who was staying in the Santa Cruz hotel in Bolivia on the night Irishman Michael Dwyer was shot dead in 2009, has contradicted the authorities' version of events.
Brazilian Marcos Brandt was staying on the same floor as the Tipperary man and claims there was no shoot-out on the night in question.
Brandt said he believes the gunfire sounded like blanks and was not consistent with cross-fire.
Michael Dwyer (24), from Brocka, Ballinderry, Co Tipperary, was killed in April 2009 during a police operation over an alleged political assassination plot targeting president Evo Morales.
Three people that police believe were planning to assassinate President Evo Morales were killed on the night.
Authorities claim the group Dwyer was with was pursued back to the hotel by police, where a shoot-out took place.
However, Brandt recalls a large explosion before a uniformed man appeared at the door to his hotel room and told him to lie on the floor.
Brandt told the Irish Times there was between two to five minutes of calm before he heard shooting. He said it was 'intense and continuous' but was not consistent with cross-fire.
Once Brandt left the room and noticed little signs of damage, he said he was convinced the police had been shooting blanks to simulate a gun battle.
Brandt's testimony contradicts the authorities' version of events, as well as the Bolivian ballistics report.
Brandt's work colleague also spoke of a similar version of events. He added that he also recalls someone pleading for their life in Spanish.
Michael's mother Caroline visited Bolivia in September for five days where she formally petitioned the government for an independent international inquiry into his death.
"If anybody ever had a living nightmare, this is it," she said at the time.
"To find out your son has been killed in the most horrific of circumstances is really difficult. We will never as a family get over this."
During her trip she visited the hotel where her son died and met representatives from the Bolivian government. She said she will not give up until she "restores Michael's good name".
Marcelo Soza, the former Bolivian chief prosecutor who is seeking refugee status in Brazil following the killing, had previously told the family that he believed Mr Dwyer was unarmed when killed. Post-mortem reports have also indicated that Mr Dwyer was unarmed.
Mr Soza also claimed there was no shoot-out in the hotel and no evidence that Mr Dwyer was knowingly involved in an assassination plot.
Meanwhile, Hungarian Elod Toaso, who was with him before his death, told a trial into his involvement in terrorism that the Irishman survived the bloody hotel raid at Santa Cruz in April 2009 and was later seen alive at the city's international airport.
He claimed Mr Dwyer was probably summarily executed at Viru Viru airport.