Police are still waiting to enter a Shropshire mansion destroyed in a blaze as fears grow for the family who lived there.

Millionaire Christopher Foster, his wife Jill and their 15-year-old daughter Kirstie have been missing since a suspected arson attack at the house in Maesbrook, near Oswestry, Shropshire, on Tuesday morning.

They went to a friend's barbecue the previous day before returning home to their £1.2 million home that evening.

Fire crews continue to dampen the house down following the blaze which began around 5am and destroyed a stable block and garage and badly damaged the house itself.

It is known Mr Foster's insulation technology firm folded last year. According to reports, bullet cartridges and pools of blood were found in the courtyard and the front door was barricaded from the inside.

Three horses were found dead while the family's dogs are also reported missing.

Police have refused to say if their investigation is a missing persons inquiry or a murder probe or comment on reports that a horsebox had been parked in front of the gates to the property as the blaze took hold, blocking the entrance to emergency services.

But search teams hope to enter the mansion Thursday evening or Friday.

Superintendent Gary Higgins said the search was likely to take several days: "It is a large property and there is a lot of debris inside which will have to be painstakingly sifted through and examined.

"This is not something which can be done quickly.

"Once we have access to the house, we will find out whether the family was inside at the time of the fire.

"Scenes of crime officers have already carried out examinations at the various outhouses."

Aerial photographs show the burnt remains of Mrs Foster's 4x4, which had the personalised number plate of JILL40 and was a familiar sight on the roads around Maesbrook.

On Wednesday evening, Mrs Foster's brother, Roger Doley, said he had been "gripped with dread" when neighbours told him what had happened.

The sales executive, from Perton, Wolverhampton, said: "When I got home and I saw a neighbour come across with her husband I was gripped with dread. I couldn't believe what she was telling me. The police called later and said they still don't know where the family are."

Worried friends have paid tribute to Kirstie, a pupil at the independent Ellesmere College in north Shropshire.

Lucy Harrington, from Shrewsbury, wrote on a newspaper forum: "Kirstie I hope you're ok. You're one of my closest friends. We have had our ups and downs as friends but you mean so much to me as a friend.

"I hope you're ok, you don't deserve it and nor do your mum and dad. Love you."

Two men stood trial accused of blackmailing 50-year-old businessman Mr Foster, but were cleared by a jury in November 2006.

About 80 officers and staff are working on the investigation, named Operation Feedback.

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