YALA, Thailand (AFP) - Suspected separatist militants in Thailand's troubled south set off an apparently coordinated series of bombs, grenades and fires early Wednesday, police said.

The first bomb exploded at around 4:00 am (2100 GMT) in front of a hotel in the centre of the town of Yala, but only parked cars and windows were damaged by the small device, they said.

Two grenades were thrown and exploded nearby, one hitting a cash machine and another damaging a billboard pole in front of a car showroom.

Police said suspected Muslim separatists also started fires at two warehouses, containing construction materials and consumer products, and a furniture shop in the town.

No one was injured in any of the incidents, they said.

More than 3,600 people have been killed and thousands more wounded in five years of separatist violence across the three Muslim-majority provinces of Pattani, Yala and Narathiwat.

Twin bombs exploded in Narathiwat in November, killing one person and injuring 70 in one of the biggest attacks on civilians since the insurgency erupted in January 2004.

Buddhist-majority Thailand annexed the ethnic Malay area in 1902, sparking decades of tension.