At least 90 militants and five security personnel were killed when ultras raided several police bases in the Muslim-dominated southern Thailand early Wednesday, officials said.

The machete-wielding militants attacked more than 15 police outposts and district offices in Yala, Pattani and Songkhla provinces in a bid to steal weapons, the officials said.

The attackers were mostly teenagers, an official spokesman said, adding that the toll might go up.

Prime Minister Thaksin Shinawatra was quoted as saying that the toll among the security forces was low because the attackers were only armed with machetes and a few guns.

Bangkok has blamed the trouble on local gangsters exploiting local Malay-speaking Muslim youths who feel few emotional ties to the predominantly Buddhist country.