Police searching for the estranged wife of a wealthy architect have completed digging up the garden of his home without finding anything.

Argentinian-born Gracia Morton, who had a cottage in Oxfordshire, has not been seen since she left her west London flat to take her daughter to school 15 months ago.

She then visited her estranged husband, Jonathan Morton, who lives in Holland Park, west London.

Police spent yesterday searching Mr Morton's home. A man was arrested and taken for questioning before being released last night.

Scotland Yard said: "The search is complete. Nothing was found. The man who was in custody has been released on police bail to return on April 14."

There was intense police activity throughout the day at the rear of the house. They put up a blue tarpaulin over the back garden and there was another in a side street to shield the officers' activities.

Police could be seen on all floors of the house and officers with sniffer dogs went in and out of the garden from time to time.

The home had been searched before, in November 1997, along with a cottage Mr Morton owned in Stonesfield, near Woodstock.

Mrs Morton, a former professional violinist, came to England 11 years before her disappearance. She went missing in November 1997. Closed circuit television pictures showed her leaving her flat to take her four-year-old daughter Celeste to nursery school.

Mrs Morton was 40 and in the middle of divorce proceedings when she went missing, and a large amount of money remained untouched in her bank.

Her sister, Constanza Lezama, said last year: "There is no reason to believe she committed suicide, she loved her daughter too much.

"And too long has passed for her to have suffered amnesia. We do not know what happened, but we are never going to give up trying to find out."

Her husband told detectives that on the day of her disappearance she had stayed for an hour at his home, then left. Her car was later found nearby.

Concern grew after the part-time charity worker failed to meet her brother-in-law and Mr Morton the following evening, and her relatives alerted police. There was no indication at her flat that she had intended leaving.

Story date: Saturday 27 February

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