BANGKOK, Thailand – Three Muslims died when attackers opened fire late Wednesday (April 11th) on the Banna Praow mosque in Pattani province, officials said.

"They were still inside the walls of the mosque when they were shot after evening prayers. We do not know the motive yet," local police officer Lieutenant Parinya Kwankaew told AFP.

A parked pick-up truck and two nearby houses were also hit by bullets, and 16 spent AK47 cartridge shells were recovered from in front of the mosque, located in Panare municipality.

On Thursday morning, a woman was injured when a man riding pillion on a motorcycle hurled a K75 grenade into her house in Yala's Raman district, The Bangkok Post reported.

More than 5,100 people have been killed in attacks across Pattani, Yala and Narathiwat since unrest escalated in January 2004, according to Deep South Watch, which monitors the violence.

A series of devastating bomb blasts in two southern cities at the end of March killed 15 people and wounded hundreds more in the deadliest attacks in the region in recent years. Police have since arrested four suspects.