Spate of attacks
Muslims make up more than 90 per cent of the two million people in southern provinces of Yala, Pattani, Narathiwat and Songkhla.
Many complain of being treated as second-class citizens in mainly Buddhist Thailand.
The area was a semi-autonomous Islamic Malay sultanate until annexed by Thailand in 1902.
The latest uprising flared in January 2004 when fighters raided an army base, killing four soldiers.
Despite martial law imposed in 2004 and thousands of Thai troops in the region, frequent attacks blamed on Muslim fighters have left around 3,500 people dead.
More than 3,700 people have died in a spate of bomb blasts and ambushes across south Thailand since an insurgency flared in 2004.
The Thai government has made little progress towards quelling the unrest despite deploying thousands of paramilitary troops - usually residents hired as armed auxiliaries to the regular military - in the area alongside 30,000 army troops.
More than 340 people have been killed this year alone.
Twelve days ago, four people were killed and more than 40 others injured in three separate attacks across the region in a single day.
The three southernmost provinces of Narathiwat, Pattani and Yala are the only
Muslim-majority areas in mainly-Buddhist Thailand and Muslims in the region have long complained of discrimination.
The groups thought to be behind the violence have made no specific pronouncements about their aims, but are thought to be fighting for a separate Islamic state.
The attacks have targeted both Buddhists and Muslims – mostly those working with the Thai government, including soldiers, police, teachers and suspected informants.
The southern provinces used to be part of a Malay-ruled Islamic sultanate until the region was annexed by Thailand in the early 20th century.