Lt-Gen Jiraphop Phuridech said that Samrann Seemaek or Bank, 34, was named in a warrant for premeditated murder after an incident in February 2009.
The Canadian man – an executive of Panorama Condominium – was shot outside his residence in Patong. A business dispute with a Singaporean had built up. A Thai woman was engaged to find a hitman to kill him, reported Siam Rath.
The suspect had kept a low profile for years but last month he had been found living in Pathum Thani.
He managed to go to ground again and was eventually cornered in a house in Hin Lek Fai sub-dictrict of Hua Hin, Prachuap Khirikhan.
He denied involvement but police say they have plenty of evidence for a conviction.
Samran was a fixer who arranged accommodation and rode a motorcycle during the crime.
Five other suspects have already been prosecuted.