Kenneth Watkinson, 48, was killed when a speeding white Porsche GT2 ran him down as he walked along a pavement at 2.30am in the tourist resort of Fort Lauderdale, Florida.

The married father-of-three was walking with his colleague, Craig Elford, 39, a father-of-two, who was also killed.

Mr Watkinson's mother, Emily Watkinson, 74, of The Oaks, in Walton Park, and her husband also called Kenneth, 86, are struggling to come to terms with the tragedy.

She said: "We are absolutely devastated – we only have to think about it to start crying. (Daughter] Anita rang me and told me – I could not believe it. We are too old to take anything like this I think."

The police in America are hunting for two people thought to possibly have been involved in an illegal street race. The damaged Porsche was later found abandoned in another part of the town.

A tearful Mrs Watkinson, a retired nurse, said: "I could kill them myself. I wish I could put my hands on them, I just wish I could. They must be mental, racing like that and taking somebody's son away from them and the other fellow as well – I hope he did not suffer."

She added: "The police think somebody picked the driver up – they should be slaughtered as well. My husband is going to kill them."

Mr Watkinson Snr said: "He was that much of a friendly and colourful character that you cannot believe this has happened. These people have broken our hearts."

Kenneth grew up with his parents and three sisters in New Lane, Penwortham, before they moved to Brookdale in New Longton. He went to school in New Longton and Penwortham before leaving school at 17, when he took various jobs, including working on a building site.

He left Preston 20 years ago and took a job working for a pharmaceutical company. He later moved to Warwickshire where he built up his own business. Kenneth and Mr Elford, from Oxfordshire, were in America to recruit people for their pharmaceutical business.

A keen fitness enthusiast, Kenneth ran the London Marathon seven times and took part in Lancashire Red Rose runs.

Kenneth's sisters, Jean Watkinson, 59, and Anne Bradshaw, 62, live in Penwortham and his other sister, Anita Dandy, 52, lives in Walton Park.

He also leaves behind his wife Kirsty and son Max, four, who live in Leamington Spa, Warwickshire, as well as children, Stephanie, 16, and Jonathan, 18.

A post mortem examination has taken place but the Foreign Office has told the family it could take more than a week before his body is returned to the UK.

Witnesses in America reported seeing two cars racing along a road near Lauderdale Beach moments before the Porsche - capable of speeds of more than 200mph - careered on to the pavement. Police say the car may have lost control at up to 100mph and did not stop.

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