TAIPEI, Jan 26 (AP) -- Taiwanese police are cracking down on pirated alien frogs featured in a popular Japanese animated film, a company official said Thursday.

The Sgt. Keroro film features five cute and funny frog characters sent from outer space to take over Earth.

The film is widely popular in Taiwan, Hong Kong, China, and several other Asian countries, and fans have queued up to buy toy representations of their heroes.

The frogs' popularity has led to rampant piracy and unauthorized downloading of the animated film from the Internet, said Chin Chi-hua, a manager of Mighty Media Co., the Taiwanese franchisee of the Sgt. Keroro copyright holder in Japan.

Police action has compelled many Taiwanese toy shops to remove the characters from their shelves, he said.

However, Chin said their effort to stop unauthorized file sharing has been complicated by several Taiwanese Web sites which have established themselves offshore to host the animation and skirt the police crackdown.