Three men were arrested Tuesday and four others were seized Wednesday, Bernama said. Yahya Ramli, the senior investigation division officer from Klang town just outside Malaysia's largest city, Kuala Lumpur, said the syndicates were accepting bets of up to 10,000 ringgit (US$2,740; euro2,175), Bernama reported late Thursday.

It was not immediately clear whether the syndicates were linked.

Police seized computers, swords, newspaper clippings, a stun gun and synthetic drugs in the raids, Bernama added. A high school student was among those arrested in Wednesday's raid, it said.

Malaysian authorities could not be immediately contacted for comment. All forms of sports betting, except for horse racing, are illegal in the Muslim-majority Southeast Asian nation. Illegal gambling during the World Cup is estimated to total billions of ringgit