This shocking photo appears to show a man throwing a greyhound into the sea - the first of two such reported incidents in just a week.
The picture was taken by a member of the public in Hartlepool, County Durham, on 26 October, and shows the man throwing the dog from a coastal structure.
Exactly a week later, the RSPCA received a separate report of a group of men repeatedly throwing a greyhound into the water. The animal welfare charity is now appealing for witnesses to either incident, after an inspector arrived too late to discover the group in action.
A campaign group claimed that the man was a greyhound trainer who had dogs tied to a rope and was throwing them into the sea and pulling them out in a cruel training practice.
In its full statement, the RSPCA said: "We are still making enquiries after we received a report that a group of men with a number of dogs were seen in Hartlepool repeatedly throwing one of the dogs - a greyhound - into the water last Thursday (2 November).
"An inspector attended the scene but the group were no longer there.
"Since then we have been contacted by a member of the public who provided photos of what appears to be a man throwing a greyhound into the water the week before (Thursday 26 October).
"Anyone who may have witnessed either of these incidents, or may have more information, should contact us on 0300 1234 999."
According to the Hartlepool Mail, in the first incident three men with nine muzzled greyhounds were seen repeatedly throwing them into the sea and pulling them out again.
Speaking about the second incident, an anonymous witness told the newspaper: "They were being carried out to the end of the structure and unceremoniously flung in from a height of about 4ft and a distance, through the air, of 6ft. The waves were quite strong and my first thought was, once they had surfaced, what if they were propelled by the crashing waves into the rusting sides of the pier? There was a significant number of dogs in the group and it appeared that they were being taken out one by one."
Greyhound protection group Campaign Against Greyhound Exploitation & Death, or CAGED Nationwide, said it had been advised through numerous phone calls that the man was a licensed greyhound trainer. The group has forwarded all the information it received to the RSPCA.