A week ago today missing woman Amanda Edwards was last seen alive and detectives have issued a desperate plea for the public to come forward with information.

There are now more than 100 officers working on the case which police say they are treating increasingly seriously.

This morning officers were set to stage a reconstruction in the car park at the West Swindon District Centre.

They are distributing 1,000 posters, printed by the Evening Advertiser, between 9am and 9pm appealing for the public's help to find Amanda.

And a car similar to Amanda's was this morning parked at the spot where her vehicle was found abandoned a week ago.

The police are to stop shoppers and passers-by in the hope of gleaning just one clue that might unlock the mystery of the 21-year-old's disappearance.

And, as day seven of the investigation unfolded, officers also visited Purton, Amanda's home village, and Calne, where she was last seen by her boyfriend, 19-year-old David Board.

Det Chief Supt Paul Howlett, head of Wiltshire's CID, said: "Thousands of people must have passed through this shopping centre last Thursday. I cannot believe that no one saw Amanda's car arrive here.

"Any information will help us understand what could have happened to Amanda. There is the danger that Amanda is the victim of a crime."

Detectives are still puzzled by what happened during the seven-hours last Thursday between when the former nursery assistant dropped off her boyfriend at his home in Bremhill, Calne, around 11.30am and then failed to make an appointment with friends later that afternoon. A family friend spotted her abandoned car in the car park at around 6.15pm.

Amanda was driving a green Rover Metro which has since been subjected to forensic tests that have not yet revealed anything suspicious.

Amanda's mother Beverley told yesterday how alarm bells started ringing when her daughter failed to return home on Thursday evening.

She went in search of her daughter herself.

"We just feel that sitting around waiting for news is so frustrating. I just feel helpless. Hopefully someone knows something and we'll get Amanda back safe," she said.

"My main concern is that Amanda is not well. She is on medication for her illness.

"To just go off somewhere is so out of character for her. It's something that Amanda would not do without letting me know where she was."

Amanda is being treated for depression and also for an undisclosed illness she contracted on holiday last year.

Det Chief Supt Howlett claims police are no closer to knowing where Amanda might be, but speculation about the man arrested on Monday evening is rife.

Detectives have until 10am today to question the Swindon man who is an acquaintance of Amanda and is being held on suspicion of kidnap. After this time they can either charge him, release him or apply for a further 36-hours extension.

Last night, Mr Board said: "We are obviously concerned about Amanda's whereabouts but I don't think it would be right to comment further."

Police have refused to confirm the identity of the man who is helping them with their inquiries.

Det Chief Supt Howlett refused to comment on specific details of the case and said that questioning of the detained man was "one of many significant lines of inquiry".

He also denied that a man had been taken to a building site in Malmesbury on Tuesday or that building sites were of particular interest to their countywide search.

Yesterday, Amanda's family were at home in Blacklands, Purton, where the former Bradon Forest pupil has lived since she was four.

The village is now home to a number of national media who have been staking out the property.

On Tuesday, the Edwards family issued an emotional plea for Amanda to return home through their family liaison officer WPC Ellie Graham.

It is believed a family member may make a public appeal in person early next week if there are still no signs of Beverley and Hartley Edwards' youngest daughter.