A man has undergone surgery after he was attacked by a dog in a country park.

A man in his 20s was walking along a footpath in Aldenham Country Park when he was approached a black dog.

The dog ripped the man's jeans and attacked his groin area during the incident, which happened between midday and 2pm on Thursday February 20.

The animal, of an unknown breed, was being walked by a woman who had five other dogs with her. She was with a teenager too.

She took the injured man to hospital in a small white van but then left without exchanging any details with the victim.

Police are appealing for any witnesses to the dog attack to come forward.

Sergeant Matthew Cann, from the Borehamwood and Elstree Safer Neighbourhood Team, said: "This was a nasty attack, resulting in the victim needing surgery and stitches.

"The woman walking the dogs is described as being in her mid forties. She was accompanied by a teenage boy and the vehicle they travelled to the hospital in was a small white van.

"I am appealing for any witnesses or anyone with information to get in touch. Any information you have, no matter how small it might seem, could be vital to the investigation. If you can help, please call the non-emergency number 101 or email me at matthew.cann@herts.pnn.police.uk quoting crime reference 41/16339/20."