US anti-piracy dogs have sniffed out 12,000 more counterfeit DVDs that led to the arrest of one person, industry officials and reports said Sunday.

Black Labradors Lucky and Flo already have a contract out on their lives after their role in a first bust of knock-offs worth millions of dollars.

The pair are said to be the only dogs in the world trained to detect chemicals used in optical discs. They were sent by the Los Angeles-based Motion Picture Association (MPA), which investigates film piracy.

The MPA's Neil Gane told AFP that Lucky and Flo sniffed out two locations in northern Malaysia on Saturday that uncovered 12,000 illegal DVDs.

Their first busts last month netted millions of dollars worth of counterfeit DVDs.

Following their success, Malaysian authorities said that piracy syndicates were trying to kill the dogs and had put a bounty on their heads.