Police officers helped witnesses retrace their steps

Ninety people returned to retrace their steps in Victoria Park, Tower Hamlets in east London on Monday, where American artist Margaret Muller was stabbed to death one month ago.

One hundred police officers and another hundred support staff mapped the positions they were in when Miss Muller was murdered, apparently at random, while out jogging at 0830 GMT on 3 February.

Detectives have also said the killer may strike again.

The park was divided into a grid and the positions of witnesses and objects were recorded - to be translated into a 3D computer picture allowing detectives to move around the park on a computer screen.

The massive reconstruction closed the park for four hours and may become the blueprint for future murder inquiries.

The only purpose we can find for Margaret's murder is the self-gratification of this killer DCS Jon Shatford

Detectives consulted with the review team looking at the murder of Rachel Nickell, who was stabbed to death on Wimbledon Common, to see how the images could have helped in that investigation.

Detective Chief Superintendent Jon Shatford said the killer may have returned to the park to avoid drawing attention to himself by his absence.

Criminal profilers have suggested the killer is a loner with low self-esteem who has difficulty maintaining relationships with women.

Mr Shatford said he may have approached other woman in the park and may have picked on 4ft 10 in Miss Muller because of her size.

Margaret Muller was a promising artist

He said the murderer seemed to strike because he enjoyed it.

DCS Shatford said: "When the motive for the murder is the self-gratification of the killer, the fear is that he will strike again."

The reconstruction will be broadcast on Monday night on ITV's Tonight with Trevor McDonald.

Miss Muller's father told the programme he had tried persuade his daughter to return to live in the US.

Erich Muller, 61, said: "Now I need to accept the fact she'll never come home again. She'll never come around and say 'Dad'."

Miss Muller came to the UK in 1998 and attended the Slade School of Fine Art.

She also worked as a teaching assistant and did some art work of her own.