St-Clair Martin Armitage says he is innocent after being arrested on Wednesday in connection with the alleged $22.5-million fraud stemming from Montreal's superhospital contract.

Armitage turned himself in to police on Tuesday at Montreal's Pierre Elliott Trudeau International Airport after arriving on a plane from England.

He's facing charges including conspiracy to commit fraud, fraud and breach of trust.

On Wednesday, he was released on $75,000 bail. He is allowed to return to England while he awaits trial.

Authorities are still working to return former hospital boss Arthur Porter and former SNC-Lavalin executive Riadh Ben Aissa to Canada.

Ben Aissa remains detained in Switzerland on unrelated charges of corruption, fraud and money laundering in North Africa.

Porter is challenging extradition to Canada from a Panamanian prison.

Others who have already been charged are former SNC-Lavalin president Pierre Duhaime; Yanaï Elbaz, Arthur Porter's associate; Elbaz's brother Yohann; Pamela Porter, Arthur Porter's wife; and Jeremy Morris, the administrator of Bahamas-based investment company Sierra Asset Management.

They all face charges of conspiracy to commit fraud, fraud and breach of trust.

Sought by UPAC since May

The British national had been sought by Quebec's anti-corruption unit, known as UPAC, since May 8 in connection to the awarding of the contract to build the $1.3-billion McGill University Health Centre superhospital project.

'I deny any wrongdoing and will continue to vigorously defend my name and reputation.' - St-Clair Martin Armitage

The lucrative contract, finalized in 2010, is the subject of an alleged fraud involving former hospital officials and former executives with Quebec engineering giant SNC-Lavalin.

On Wednesday, Armitage released a statement in response to the allegations against him.

"I deny any wrongdoing and will continue to vigorously defend my name and reputation," he said.

"I am deeply saddened by the allegations of conspiracy and fraud surrounding the McGill University Health Centre PPP project."

Armitage said he has devoted his life to working in the public service.

He said he has co-operated with authorities and said he would not be making any more comments until the court proceedings are over.

With files from The Canadian Press