Macabre new twist in hunt for artist's killer

Detectives are investigating a macabre twist in the murder of US artist Margaret Muller.

Criminal profilers say the man who carried out the frenzied attack may have killed for pleasure before, using animals as his victims.

In America police have established that some serial killers have a history of animal abuse.

Detectives here believe it is the first time the possibility has been actively considered during a murder investigation in Britain.

Ms Muller, 27, was stabbed repeatedly in the back as she jogged through Victoria Park in Hackney in February.

Police have ruled out anything in her personal life that could have prompted a motive and have no evidence she was stalked.

They believe she was murdered at random by a killer who took pleasure in the act. They also believe the killer will strike again if he is not caught and have issued a £15,000 reward for any information that could lead to his arrest.

Detective Chief Superintendent Jon Shatford, who is leading the hunt, said: "We believe this killer is turned on by the act of stabbing and that he may have started on animals. We are looking for cases where animals have been stabbed and killed - maybe during a burglary."

The murder inquiry has become the biggest in London with about 40 detectives involved. They are still seeking a white man in a luminous orange and yellow top seen jogging alongside Ms Muller.

The profile of the killer is a loner in his early twenties.