STOCKHOLM (AFP) - The Swedish producer of the Ikea meatballs found to contain horsemeat said it filed a police report on Monday against a Swedish supplier that bought the tainted meat from two Polish abattoirs.

"We don't know where in the chain the crime has been committed," said Mr Ola Larsson, a spokesman for Dafgaard, which produces most of the frozen meatballs sold by the Swedish furniture giant in Europe.

"Evidence has been handed over to the authorities," the company said in a statement.

The supplier produces five to 10 per cent of the beef used by Dafgaard, according to the company, which last week confirmed it had found traces of horse in several batches of its meatballs.

"Dafgaard has with the help of DNA analysis secured evidence showing that the supplier has mixed horsemeat into beef, despite previous guarantees to us that they don't handle horsemeat," it said.

"The supplier in question has delivered the (meat) to all four production batches where traces of horsemeat were found." Ikea last week pulled its one-kilogramme bags of frozen meatballs off shelves in 25 countries after Czech authorities said they found equine DNA in the product.

The furniture retailer was the latest group to become caught up in a Europe-wide scandal over horsemeat in food products that erupted in January when horse DNA was detected in beefburgers in Britain and Ireland.