COPENHAGEN (AFP) - A listeria outbreak at a small meat producer outside Copenhagen has killed 12 people in Denmark over the past few months, the country's food safety regulator said on Tuesday.

"The company has therefore been closed and all its products are being withdrawn," the Ministry of Food, Agriculture and Fisheries said in a statement.

The agency's infectious diseases unit had notified it in June that a listeria outbreak could be under way, and on Monday the source was identified as a deli meats poducer in Hedehusene, around 30km west of Copenhagen.

The bacteria had been found in a batch of Danish head cheese known as "rullepoelse", which was pulled from shelves in May.

The first case of listeria linked to the tainted product was registered by the authorities in September last year. Since then 20 cases have been reported, with 15 people falling ill since June.

Listeria can linger for weeks even in cold temperatures like a refrigerator. A person can get sick up to two months after consuming a contaminated product, and infections typically cause fever and muscle aches.