A man has been arrested in the stab murder of a wealthy City director in his Chelsea home.

Scotland Yard confirmed that the suspect was seized in a west London street at 9pm yesterday, less than a day after the attack on bonds dealer John Monckton and his wife, Homeya.

Two youths broke into the couple's multi million pound home in Upper Cheyne Row at 7.30pm on Monday and overwhelmed them. Their nine-year-old daughter, who was in the house, phoned the police.

Mr Monckton, 49, died in hospital from stab wounds and his wife is in a serious condition in hospital after she underwent "significant" surgery.

The Legal and General director was a cousin of Rosa Monckton, close friend of Princess Diana and wife of Daily Telegraph editor Dominic Lawson.

A suspect is being quizzed at a west London police station, but detectives are still seeking a second man.

"For operational reasons we will not be providing any further information, as extensive enquiries are ongoing which we do not wish t o jeopardise," a spokesman said.

The attackers fled via Glebe Place to the fashionable King's Road.

Police urged anyone who saw them, or who were in the area at the time, to call the incident room on 020 8358 0400, or Crimestoppers anonymously on 0800 555 111.