One of the Britons held for four days after last Saturday's police raid in Genoa today said he planned to sue the Italian authorities.
Mr Norman Blair (38) who says he was "kidnapped and tortured by the Italian state", was among several hundred people who yesterday took part in a demonstration outside the Italian Embassy in London.
Today Mr Blair, originally from Newport, south Wales, and now living in Haringey, north London, told BBC 1's Breakfast with Frost programme: "I have contacted lawyers in Italy and I'm going to be taking legal action against the police in Italy, as is everyone else who was arrested in that school that I have talked to."
Mr Blair and four other Britons allege that they were badly beaten in the raid on a school which was being used as the headquarters of the protest organisation, the Genoa Social Forum. The raid followed two days of ferocious anti-G8 rioting in the Italian city.
Foreign Secretary Mr Jack Straw is examining claims that the Britons had to wait longer than Spanish detainees for meetings with their national consuls.
Mr Blair, Mr Daniel McQuillan (35), Richard Moth (32), from north London and his girlfriend Nicola Doherty (27), were released after appearing before a magistrate on Wednesday.
The other freed Briton, Mr Mark Covell (33), from London, remains in an Italian hospital where he is being treated for internal bleeding and broken ribs.
Today Mr Blair insisted that he had not been put off protesting by his experience.
"I'm not scared or intimidated. They wanted to break me, and I'm not broken, and I feel strengthened and inspired by the strength of our movement around the world."
PA