Today, forensic officers in white overalls were going in and out of number 44, where Miss Yeates and Mr Jefferies lived.

A silver Chrysler which was parked on the road outside the house was lifted on to a lorry to be towed away.

Yesterday, police released CCTV of Miss Yeates buying two bottles of cider from an off-licence as she walked home on December 17 - the night she was last seen alive.

The footage, which shows her smiling as she entered the off-licence, was revealed as Crimestoppers announced it is offering a £10,000 reward for information which helps catch her killer.

Wearing a white winter jacket and carrying a black bag, she looked carefree as she strolled into the shop on Regent Street.

Forensic officers have taken away bags of evidence from Miss Yeates's flat and the blue front door for further tests.

Police are pursuing a number of lines of inquiry, including the possibility that there was a sexual motive behind Miss Yeates's killing or that she knew her killer.

Police are also keeping an ''open mind'' about whether Miss Yeates had been held captive or was killed where she was found.

Mr Reardon, who reported her missing on Sunday night after returning home from a weekend away in Sheffield visiting family, was being treated as a witness and not as a suspect.

Detective Chief Inspector Phil Jones, who is leading the murder investigation, said his officers were following up several new leads following yesterday's appeal.

''There are a number of lines of inquiry we are following up. One of these concerns apparent reports that several people were seen or heard in or around Joanna's flat on the night of her disappearance,'' he said.

''As I stated yesterday, we know that there were a number of people in the Canynge Road area on the night of Joanna's disappearance.

''We want to hear from any of these people or anyone else with information that can help the inquiry.''

Mr Jones said he was keeping Miss Yeates's parents, David, 63, and Theresa, 58, and brother Chris, up to date with the inquiry.

mfl