A British fraudster claimed he was a quadriplegic and faked being in a coma for two years to escape prosecution for a $73,000 theft.

Alan Knight, 47, of Swansea, was finally caught out when stunned doctors spotted him eating, wiping his face and even writing, Metro reports.

Further investigations uncovered CCTV footage of Knight pushing a shopping trolley around a Tesco supermarket and driving.

It is alleged he fabricated the injury in a bid to avoid punishment after conning an elderly neighbour out of their savings.

The father-of-three's wife, Helen, kept up the act by tending to her "vegetative" husband.

"In my entire career this is the most calculated, long-term deception of a vulnerable, elderly neighbour I have ever seen," Detective Constable Paul Harry, from South Wales police, said.

Knight pleaded guilty to 19 counts of theft and forgery.