One of Commodore Frank Bainimarama's former colleagues has alleged the self-appointed Fijian prime minister badly beat a group of female pro-democracy advocates during his 2006 coup.

Lieutenant Colonel Ratu Tevita Mara, once a high-ranking army man in Fiji, fled his homeland earlier this month after being charged with trying to overthrow the government.

While hiding out in Tonga, he has hurled a barrage of controversial claims at the regime, which he played a senior role in after it seized power at the end of 2006.

In a statement released today, Lt Col Mara alleged that during the coup almost five years ago Cdre Bainimarama would take protesters to an army barracks and assault them.

"If he was not attacking their bodies, he was attacking their property," he said.

Lt Col Mara said one night three women who were part of the Fijian pro-democracy movement were brought to the barracks where Cdre Bainimarama, dressed in civilian clothes, and a number of other soldiers were waiting.

"The men were hanging back unsure what to do," he said.

"This was the first time there were women in the camp needing to be silenced.

"Bainimarama landed the first blow. He then continued to punch and kick them.

"When they had fallen to the ground he jumped on their backs and continued with the beating."

Lt Col Mara said the women couldn't see who was attacking them and it had long been blamed on another former senior military man, Brigadier General Pita Driti.

He said while he was there for the beatings, he did not participate in them.

Lt Col Mara claimed he didn't try to stop Cdre Bainimarama because he was a lower rank than him.

"But that is not really a good reason and I regret I did not do more," he said, apologising to the women and promising to answer to them in person when he returned to Suva.

Lt Col Mara added that he had only ever seen Cdre Bainimarama hit women and never men.