Detectives are appealing for information that may help catch the killer of Katerina Koneva - six years after she was murdered by an intruder at her home in Iffley Road, Hammersmith, on Thursday, 22 May 1997.

Police are offering a £20,000 reward for information leading to the arrest and conviction of her killer.

The intruder was disturbed by her father, Trajce Konev, when he returned home at approximately 16:40 that day. The front door of the house was open, and the door to the first floor living room was jammed shut. The suspect fled the scene by jumping from the first floor window. He then ran off with Mr Konev in pursuit.

When Mr Konev returned home after losing the suspect in the streets of Hammersmith, he found Katerina's body lying on the living room floor. She had been strangled.

The suspect is described as being a pale skinned man of Eastern European appearance. He is short, between 5' 2" and 5' 4", and was described as being stocky and muscular. In 1997 he was aged between 40 and 50. He was balding, with dark hair, which was greying at the sides. He is described by witnesses as having a foreign accent.

After the suspect ran away from the family home in Iffley Road, he ran into Hebron Road, Agate Road, then Amor Road, and through a builder's yard where he was captured on CCTV camera. This is the only image that police have of the suspect.

He then ran through Hammersmith Grove into Trussley Road where he hijacked a black Fiat

Uno, threatening the female driver with a knife. Because of heavy traffic, he then abandoned the car and got on a bus which took him to Hammersmith Broadway, where he was last seen.

Katerina's murder has been linked with two other incidents in the Hammersmith area early in 1997, where two 12-year-old girls were followed home by a man fitting the description of the suspect.

One incident happened only half an hour before Katerina was murdered. Police were contacted by a member of the public who said he had observed a 12-year-old girl being followed as she walked home in Aldensley Road, W6. The man watched the girl as she went into her home then walked away.

The other incident happened on the afternoon of 4 February 1997 when a 12-year-old girl was followed by a man in Brackenbury Road, W6. She noticed him and ran into her house. The man rang the doorbell at the address, which the girl ignored and the man went away. Two days later the same man tried to gain entry to the house - he knocked at the door and when it was opened by the girl's mother he went away.

Police are keen to hear from anyone who recognises the description of the suspect, and are anxious to speak to anyone who may have been similarly followed by this man.

DCI Norman MacKinlay, who is leading the murder investigation, said: "It has been six years since this innocent young girl was murdered by an intruder in her own home.

"We are appealing for anyone who may know this man to come forward. Do you know him? Do you know where he is? Have you ever dealt with him in an official capacity - maybe as an employer, a police officer, or immigration officer?

"Maybe you do know him, and there were reasons in 1997 why you did not come forward then. Those reasons may not be so pressing now, and we are appealing for anyone who knows anything about him to call us.

"I would dearly like to be able to arrest and convict the man who killed Katerina. We need your information.'