Thoonglung police chief Col Vichaphan Chanthraporn said investigations showed that the deceased owed about 35 million Baht (RM4mil) to a businessman from Malaysia.
"The deceased tried to pay the debt by issuing a cheque to the other party.
"However, the cheque bounced which caused great anger to the other party who filed a case against him in a Thailand court.
"The case is still pending since six months ago," Col Vichaphan said.
He said the money was believed to be over sales and purchase of land in Thailand.
The Star reported that businessman Lee Ah Han , 54, was shot dead at noon on Friday near Ban Khlong Pom in Kanchanawanit along the Sadao-Hatyai Road, southern Thailand, about 45km from the Malaysian-Thai border.
He was said to be driving his Thai-registered car accompanied by a woman heading to the Hat Yai airport.
Two gunmen in another car fired several shots, believed to be from a M-16 rifle, at the car Lee was driving.
The woman was injured in the incident and was rushed to the Prince of Songkhla University’s Hospital in Hat Yai for treatment.
Col Vichaphan said the deceased was involved in a few property projects. He also acted as a middle man in land purchases at Danok.
"He was a former owner of one of the hotels in Danok,” said Col. Vichaphan adding that the woman could be linked to the killing.
Lee, known as Ali Baba by local Thais, was originally from Jalan Yakin, Alor Setar, Kedah.
He sustained several gunshot wounds to his head and died at the scene.
Lee had migrated to Bangkok several years ago with his wife, in her 40s, and their two daughters, in their 20s.
The shooting left about 10 bullet holes on the driver’s side window and several on the left front windscreen and passenger's side window.
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