NARATHIWAT, Thailand (AP) -- Marines fending off a militant assault on their base in Thailand's violent south killed 16 insurgents in an overnight shootout, authorities said Wednesday. It was the deadliest toll the Muslim guerrillas suffered since more than 100 died in a single day nearly a decade ago.
Thailand's military has struggled to control the insurgency since it flared in the country's Muslim-majority southernmost provinces in 2004.
About 30 militants attacked the marine base in Bacho district in Narathiwat province just after midnight, said Capt. Somkiat Ponprayun, the provincial marine corps special task force chief.
The shootout ended with 16 militants killed and the rest fleeing, Somkiat said. The death toll was reduced from an initial figure of 19 given out earlier Wednesday by a regional army spokesman.
Somkiat said the insurgents -- most of them armed and wearing flak jackets -- opened fire at the base and were counterattacked by the security forces. Authorities confiscated 13 rifles, three pistols and a pickup truck at the scene.
Violence has occurred nearly every day in Thailand's three southernmost provinces since 2004, and more than 5,000 people have died. Security forces as well as teachers have been targeted by insurgents because they are seen as representatives of the government of the Buddhist-dominated nation.
Muslims in the deep south, which was once independent, have long complained of discrimination by the central government in Bangkok, and the insurgents are thought to be fighting for autonomy. But the insurgency remains murky, with militants making no public pronouncements on their goals.
Somkiat said the marines who fended off the attack suffered no casualties because they had been tipped off by local residents and had prepared for the assault.
The losses Wednesday were the most since guerrillas launched simultaneous attacks on police stations and checkpoints in the three provinces in April 2004, triggering clashes in which more than 100 militants were killed, 32 of them at a mosque in Pattani.
The government has attempted to gain support from local residents and separatist sympathizers in solving the insurgency, but progress has been slow. However, experts say militant attacks on soft targets such as teachers and civilians may have made villagers turn to the authorities.
"Some sympathizers are now fed up with the widespread, unspecific killings from the militants because they, too, are affected by the losses," said Jaran Maluleem, a Muslim expert and political scientist at Thammasat University in Bangkok. "Still, the government must be able to explain to the public why this mass killing of insurgents is justified."
Prime Minister Yingluck Shinawatra said the government will provide protection to the civilians who gave information about the raid to authorities.
"We must not be negligent and must solve the problems at their roots. These issues are sensitive and should be discussed among those living in the area," Yingluck said.
Narathiwat is about 800 kilometers (500 miles) south of Bangkok.
On Sunday, suspected militants killed five soldiers and wounded five others in two attacks that included a car bomb that exploded in Yala province as a truck carrying six soldiers passed by. The militants then opened fire on the soldiers, killing five, and took the dead soldiers' rifles.
Associated Press writer Thanyarat Doksone in Bangkok contributed to this report.
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