THE hunt for missing 21-year-old Amanda Edwards continued at the building site of the former Knoll House Hotel at Malmesbury on Tuesday.

Nursery assistant Miss Edwards, of Blacklands, Purton, went missing last Thursday after dropping off her boyfriend David Board, 19, in Bremhill at 11.30am.

A Swindon man arrested on suspicion of kidnapping is believed to be a builder at the Knoll House development.

A forensic team searched the grounds, a skip and inside the building of the former hotel at Swindon Road from 9am Tuesday morning until early afternoon.

A man hidden under a white sheet was driven into the building site in an unmarked police carrier later the same day.

A woman police officer in the front seat videoed the man with a camcorder, but the car left the scene in seconds, heading towards Swindon.

A police car is now on 24-hour guard at the site and police say the area has not been ruled out from their enquiries.

The man leading the investigation, Det Ch Supt Paul Howlett also revealed that enquiries were ongoing at the site, but that a decision was yet to be made on whether to apply for further questioning time with the man, or release him.

The former hotel is being converted into 14 houses by Chase Homes.

Chairman Chris Kent said: "The police have come on the site. They asked our permission to do that and we have been fully cooperative with the investigation."

Police said the former hotel site was one of a number in Wiltshire being searched. A police team was due back there last night to continue the search.

Miss Edwards works at Little Foxes Preschool, Brinkworth, as a nursery nurse. Owner Ken Willy said: We are quite devastated. Our support is with Amanda's family at this time and we have sent them our best wishes."

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

Learning she had not met friends as planned that day and after hearing that her car had been spotted at a car supermarket car park, she went in search of her daughter, but found only her dark green Rover Metro with the registration L597 PHP abandoned in car park C at Asda in Swindon.

"My main concern is that Amanda is not well. She's on medication for her illness," said Mrs Edwards.

"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.

"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."

Yesterday the task force hunting for Amanda was upped from 60 to 100 officers. DCS Howlett said the Asda in West Swindon, where Amanda's abandoned green Rover Metro was discovered, remains a key location in the investigation. Officers will be out in force today from 9am to 9pm, handing out pictures of the missing girl in an effort to find anyone who may have seen her the day she disappeared.

Officers will also hand out leaflets and talk to shoppers at the One-Stop-Shop in Purton, where images of her buying a pack of cigarettes were recorded on the store's CCTV cameras on the morning of the day she vanished.