The South London police have launched an official hunt for heartless thugs after a swan was found with its neck covered in blood.
Authorities believe the swan was shot with an airgun.
The police reportedly found the injured swan with air pellet injuries in its neck at the Southmere Lake near Thamesmead.
Investigations revealed that the swan had a pellet on the right side of its head.
The Thamesmead East Police Team is currently urging its visitors to be aware of the incident when visiting the Southmere Lake Park.
Some of the swans that are along the River Thames are owned by the Crown.
They are also protected under a special decree.
Wild birds are protected under the law and they are not allowed to be hunted or harmed by humans.
Anyone with information about the incident are urged to contact 101 using the crime reference 3911330/20, said the Greenwich Police.