In Thailand's largely Muslim southern provinces, gunmen have killed a police officer and an official, as violence continues in the troubled region. The latest deaths came a day after the arrest of several men accused of planning attacks on officials.

A Buddhist police officer and a Muslim government official on Tuesday became the latest victims in the bloodshed in Thailand's southern provinces.

Police say a passenger on a motorcycle shot and killed the traffic officer as he drove to work in Pattani province. The government official was killed in nearby Yala province.

Thailand's population is 90 percent Buddhist. About 7.5 million Thais are Muslims, and they live predominately in the southern provinces.

Officials have blamed the latest killings on separatists. This year, several hundred people have been killed in violence in the south - most of them government workers, police officers and Buddhist monks. More than a hundred suspected militants died in a police attack earlier this year.

Human rights groups say the security forces' heavy-handed efforts to quell the unrest have undermined local confidence in the government's dealing with the violence.

Tuesday's deaths came a day after police arrested several men suspected of planning to attack government buildings and threatening to kill officials.

Security forces also arrested two men accused of attempting to bomb an army patrol in Yala province.

Thai Prime Minister Thaksin Shinawatra said the men arrested Monday belonged to Muslim separatist groups.

Panitan Wattanayagorn is a political scientist at Thailand's Chulalongkorn University's Institute of Security and International Studies. He says the attacks reflected the growing cooperation between several separatist groups in the south. Several of the groups are linked together under the umbrella organization Bersatu.

"Several other organizations participated in these activities to further their own causes but they have been organized, they have been directed, they have been coordinated by perhaps the main groups under the umbrella of the Bersatu," he said.

Professor Panitan says he expects more attacks in the coming weeks as security forces in the south are increased.

The Thai government earlier this month planned to meet with the leader of Bersatu, Wan Abdul Kadir Che Man, who lives in Malaysia. But the talks were canceled after there were new attacks in the south.