A Greater Manchester animal sanctuary is being investigated over claims it is used as a slaughterhouse for unwanted racing dogs.
A greyhound racing watchdog has started an investigation
A Sunday newspaper reported staff at the Leigh Animal Sanctuary near Wigan killed healthy greyhounds after their careers on the racetrack were finished.
A spokesman for The National Greyhound Racing Club (NGRC), which runs the sport, said it was investigating.
The animal sanctuary has refused to comment on the claims.
The group's senior steward Edward Bentall said: "The rules of racing are very clear for all to see that every effort must be made to re-home and avoid the euthanasia of greyhounds, which in any case must be carried out by a registered veterinary surgeon.
"Any person who is unable to abide by the basic rules for greyhound welfare is not welcome in NGRC racing."
The report in The Sunday Times said workers at the sanctuary, on East Lancashire Road, had offered to destroy two healthy young greyhounds by lethal injection for £70.
The newspaper also reported that the sanctuary was well-known within the sport and had been offering the service for many years.
The sanctuary's website said it "takes no account of the reasons for the animals becoming unwanted or homeless, preferring to focus on the more important task of providing them with a secure future".
In July, a Sunday Times investigation claimed David Smith, a builders' merchant in Seaham, County Durham, had shot about 10,000 dogs with a bolt gun in the past 15 years.
RSPCA veterinary spokesman Steve Cheetham said the greyhound industry needed to "clean up its act".
He said: "This is totally unnecessary slaughter. There is no justification for killing these animals simply because they can't do their job.
"Animals should be their owner's responsibility for life, not just until they reach the end of their usefulness.
"This is a sad reflection on the greyhound racing industry which should be cleaning up its act."