The parents of a British man killed in a suspected mugging in Switzerland have paid tribute to him.

Commodities trader Tom Lamb, 28, died in hospital from a brain haemorrhage a day after being punched in the head in the city of Lucerne.

Local police believe he was the victim of a bungled street robbery.

His parents, Jenny and Jeremy Lamb, described their son as a "kind soul" and said they had lost "a unique individual".

Mr Lamb, a former Harrow School pupil, was visiting friends in Lucerne when he was killed last month.

He had lived there for six years while working for multinational commodity trading company Trafigura before being posted to Shanghai in China, and hoped to return to Switzerland.

Lucerne police said Mr Lamb was attacked as he walked home with a friend in the early hours of Saturday, October 25.

A group of four men approached the pair and, after exchanging a few words in English, one of them punched the British trader.

Mr Lamb was taken to hospital but died from his injuries the next day.

His father, 64, said: "As soon as he went down, it was obvious that something was seriously wrong and they just ran off."

Swiss officers arrested a 23-year-old Tibetan man on October 27.

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