A replica bronze sculpture of Olympic champion Steve Ovett has been sold to a scrap yard in an elaborate sting for a television documentary into the soaring rate of metal thefts across the UK.

Sculptor Peter Webster, whose original life-sized £25,000 statue of the Brighton-born middle distance runner was stolen from the city's Preston Park in September, agreed to make a one-off likeness of the athlete's face for ITV1's Tonight With Trevor McDonald programme.

A metal merchants took the bait and bought the artwork as scrap for just £30 while being secretly filmed, despite the undercover reporter telling them that it was part of the stolen statue.

The 30-stone figure was hacked from its plinth almost five months ago at the park where Ovett used to train.

Police believed it was stolen to melt down for scrap.

Mr Webster said he was surprised the scrap dealer who bought the new face he sculpted did not question the Tonight team about where it had come from because handling stolen goods was a criminal offence.

He said: "The sculpture itself has been in the national and regional press, so you would have thought that people would raise some questions about why parts of an athlete, a face, are being sold."

Speaking about the theft of the original statue, Mr Webster, of Preston Circus, Brighton, added: "It was upsetting. I was bitterly disappointed about it and felt disbelief because of the amount of work that I had put into it and the fact that it was a sculpture for Brighton.

"Steve is very much associated with Brighton and that part of the park as well because that's where he used to train."

Mr Webster spent four years creating the statue, which was unveiled in 1987.

The TV documentary, which is broadcast tonight, discovered that metal theft has increased by 170 per cent in parts of the UK in the last year alone because demand for lead is at a 27-year high and copper has quadrupled in price in two years.

British Transport Police told the Tonight programme that it was their biggest problem after terrorism and that they had set up a national taskforce to tackle it.

Railway cable theft is costing the rail companies millions of pounds and caused commuters 240,000 minutes of delays to their journeys in 2007.

Thieves are targeting lead roofs and even graveyards and crematoriums to steal metal.

Tonight used hidden cameras to film at four licensed and registered scrap yards in the West Midlands to sell them a series of dubious metal items from "the back of a lorry", including brass doorknobs, road signs, drain covers and even an entire bus shelter, as well as the figure of Ovett, who won the gold medal in the "race of the century", the 800 metres at the 1980 Moscow Olympics against arch-rival Sebastian Coe.

Under the trade's regulations, licensed scrap dealers must take down the name, address and vehicle registration of every person that sells them goods, but Tonight found that this practice was not always followed.

The undercover reporter was not challenged by any of the four scrap yards about where his goods had come from.

Concerns over the high rate of metal thefts have prompted calls for new legislation to encourage scrap yards, where the thieves sell their goods, to keep a better record of their suppliers.

Sgt Mark Seales, of British Transport Police, told Tonight: "It's a lucrative business, there's a lot of money in it, and obviously there will be some people who will take things, no questions asked."

The identities of the four scrap yards targeted, including the one that bought the Ovett replica, will be revealed on the programme.

Tonight: The Great Drain Robbery is on ITV1 at 8pm today.

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