YALA, Thailand (Reuters) - Five rebels were killed in Thailand's rebellious Muslim far south after militants launched a spate of gun, arson and bomb attacks on Wednesday, killing four and wounding at least 12, police and soldiers said.

Police said they found five bodies of men aged between 25 and 30 after clashes in a rubber plantation in Yala, one of the four southern provinces where more than 2,300 people have been killed in the three-year insurgency.

Four M-16 rifles and combat gear were also found at the site, a police officer involved in the clashes told Reuters by telephone.

Earlier on Wednesday, militants shot dead two soldiers and wounded another as they patrolled a rail track in Yala.

The attackers escaped with two M-16 rifles and a pistol, police said.

The attack came shortly after 400 police and soldiers raided 17 targets in the capital of Yala province, but found only four guns and no suspects, an army spokesman said.

In Narathiwat province, insurgents set off a bomb hidden in a motorcycle parked in a busy market, killing a Buddhist woman and wounding 11 other shoppers.

In Songkhla, a policeman was killed and a pedestrian was wounded by a bomb hidden in a motorcycle parked next to a traffic kiosk, police said.

Other violence, including an arson attack on a petrol station and bombs hidden in rubbish bins, caused some damage but no casualties, police said.

Since last month, security forces have launched almost daily raids on suspected insurgent hideouts in villages and towns and have detained nearly 400 people without charge.

Human rights groups are critical, saying detainees are exposed to potential abuses by the army, which is operating under martial law that grants soldiers immunity from prosecution.

Since taking office last year after a bloodless coup, Prime Minister Surayud Chulanont has fought off pressure from the Buddhist majority to take stronger action in the Malay-speaking region, saying he remains committed to a peaceful resolution.

He has apologised for the harsh policies of ousted predecessor Thaksin Shinawatra and promised restraint in dealing with the violence.

But he has had no more success than Thaksin in dampening the violence in the region, a former Muslim sultanate annexed by Thailand about a century ago.

REUTERS