Murder hunt breakthrough

Detectives hunting the killer of a teacher stabbed to death after he confronted a burglar believe a suspect has been caught on CCTV.

Father of two Robert Symons, 45, bled to death from a single stab wound to the heart as he tried to protect his family at his £1 million home.

Officers have found a kitchen knife, understood to be the murder weapon, near the house in Airedale Avenue, Chiswick. Forensic tests are being carried out on the knife and detectives are investigating whether it was brought by the intruder or if he grabbed it from the family's kitchen. A police source said: "We urgently want to trace a man leaving the house who was captured on CCTV. He could hold the key to solving the murder."

The killer may also have attempted to break into another house in the street. He may have had an accomplice and police conducted house-to-house enquiries to find witnesses who saw anyone rush from the house at about 4.30am on Wednesday.

Mr Symons's wife Linda and daughters Harriet, four, and two-year-old Melissa were with liaison officers yesterday and will be interviewed about the killing later today. Detective Chief Superintendent Andy Murphy said a suspect seen leaving the house was white, wearing a light short-sleeved shirt.