One police officer was killed and four others were injured in an explosion at a police checkpoint in southern Thailand.

The local cops were manning a security post along Highway 43 in Pattani province when the bomb was detonated on February 4.

Police Corporal Anucha Khwanthongon was killed when a piece of shrapnel fatally pierced his neck.

Police Corporal Thanapat Thongchai suffered severe injuries with shrapnel embedded in his arms and legs, tearing his limbs open and exposing bone.

Three others identified as Police Sergeant Major Chatmongkhon Nuchsri, Police Sergeant Major Noppol Raksapram, and Police Lance Corporal Kilarat Thongma had minor injuries.

The survivors were taken to the Nong Chik Hospital for treatment.

Police Colonel Pattanachai Palasuwan, superintendent of the Nong Chik District Police Station, said an explosive ordnance team was surveying the area.

He said: 'I have ordered the relevant officers to conduct a thorough sweep. We believe the motive was to cause unrest in the area.

‘All units near the southern border have been ordered to be on high alert, especially security units protecting teachers and vulnerable groups. Our security intelligence unit continues to report that insurgents are still scattered around the area and aiming to cause more disturbances.'

Islamic separatist terror attacks target the three southernmost provinces of Thailand - Yala, Pattani and Narathiwat - next to the border with Mulsim neighbors Malaysia. Thai state employees and infrastructure are often hit while attacks on civilians are rare.

Officials believe the conflict dates to a deal in 1909 that the British Empire struck to incorporate the Muslim region into the Siamese mainland.

The region's culture is more similar to Malaysia and dramatically different to Buddhist Thais causing decades of tension that lead to the emergence of separatist groups fighting for independence in the 1960s.

The struggle has continued ever since with more than 7,344 people killed and 13,641 injured between January 2004 and March 2022.

The British Foreign & Commonwealth Office warns against all but essential travel to the region while Canada's government warns its nationals to 'avoid all travel' to the three provinces.