THE wife of a North Yorkshire racehorse trainer arrested along with reigning champion jockey Kieren Fallon in a nationwide police investigation into race fixing said last night: "He is innocent."

Middleham trainer Karl Burke was arrested in a dawn raid yesterday morning. He was one of 16 people arrested over allegations of race fixing.

And last night Fallon denied any wrongdoing after being released on bail.

City of London Police carried out raids in North Yorkshire, South Yorkshire, Hertfordshire and Suffolk, seizing papers and computers, which were taken away to be examined by experts.

Three jockeys were arrested: Fallon, Fergal Lynch and Darren Williams, who regularly rides for Mr Burke.

Fallon, who won this year's Epsom Derby, is the country's most successful jockey. He made his name on the northern tracks while riding for Thirsk-based Lynda Ramsden before moving to Newmarket to ride for Henry Cecil and then Michael Stoute.

They were all taken to police stations near their homes and questioned on suspicion of conspiracy to defraud.

Last night, City of London Police said that some of those arrested were members of a racing syndicate, and added that the case was of great national significance.

Mr Burke was arrested after returning from his 20th wedding anniversary celebrations.

Speaking from their racing base of Spigot Lodge, near Middleham, his wife, Elaine, said: "We've just had our best season ever and they are accusing Karl of race fixing.

"This is something he's totally innocent of. We've had this before in racing and it all came to nothing. It just messes up everybody's life. It's a nightmare for the whole family."

James Bethell, chairman of the Middleham Trainers' Association, said Mr Burke's arrest had come as a great shock.

"If the integrity of trainers is in question it's got to be a bad day for racing," he said. "The good news is that people are investigating. If there is any skulduggery they will find it.

"Karl has been in Middleham for three or four years and is a member of the association.

"I have always found him a good man to work with, which makes this all the more unbelievable."

Middleham trainer Andy Crook was also very surprised at the arrest. He said: "Karl's had 50 winners this year and was well up in the trainers' table. I hope for him and his family he will be in the clear. We will rally round him and do everything we can to help."

News of the arrests caused shockwaves throughout the racing community. All three jockeys had been due to ride at York yesterday but were replaced at the last minute.

The police investigation centres on suspicions of corruption within horse racing and fixing the outcome of races.

It was sparked by the Jockey Club after it was given information by online betting exchange Betfair.

Gamblers using betting exchanges can back horses to win, but also "lay" them to lose.

Jockey Club director of security Paul Scotney said: "Earlier this year, it became apparent that what had started out as an investigation into possible breaches of the rules of racing had uncovered evidence which indicated criminal activity which could undermine the integrity of horseracing. Consequently, we decided to refer the matter to the City Of London Police.

"Our decision also took account of the fact that the Jockey Club has no powers of search or arrest and has limited powers when investigating individuals not bound by the rules of racing."

At 5pm, 12 of the 16 arrested, including Kieren Fallon, were bailed by police to appear at a London police station in two months' time. Fallon, 39, left Bury St Edmonds police station at 5.30pm.

The remaining four were still in custody last night.

Detective Chief Superintendent Steve Wilmott, the officer in charge of the operation, said: "We now embark on the long haul of analysing all the additional information we have gathered today. The computer evidence alone will require a significant investment in time and resources."