Shoppers were faced with piles of rotting fish when Greenpeace created a stink at three major supermarkets in Oxford.

Campaigners, dressed as fishmongers, yesterday called at Tesco in Cowley, Asda in Wheatley and Morrison's in Banbury in a bid to stop selling 'beam trawled' products.

Greenpeace says the method - where a net kept open by a beam is pulled along the sea bed - is environmentally damaging. Up to 70 per cent of the catch is incidental - and has to be thrown away.

The protest comes a month after the environmental group staged a 35-hour demonstration at Didcot Power Station, which cost owners npower about £500,000. The protest ended 36 hours later when npower were granted a High Court injunction.

Oliver Knowles, Oceans campaigner for Greenpeace, said: "Beam trawling is particularly destructive to the environment and is very wasteful.

"Over the last few weeks we have been asking supermarkets in the UK to stop selling these products.

"The good news is we have persuaded Marks & Spencer and Waitrose not to do it."

A Tesco spokesman said: "We are committed to the principle of sustainability in our fish sourcing."

Our picture shows a young shopper at Tesco in Cowley with some of the dumped fish.