Ms Benjarat was last seen leaving her house with a man driving a grey Bangkok-registered Toyota pickup truck. She told friends that she was going to resolve a dispute with a relative over car repayments.
Concerned for her safety, her mother reported her missing to Chalong Police the next day.
Ms Benjarat’s body was found in an area beside Petchkasem Rd in Moo 1, Tambon Nong Prong, Khao Yoi District, Phetchaburi, three days later, last Friday (June 7).
Police took Anuwat Pimmat, 22, into custody at an eatery in Tambon Thongchai of Bang Saphan District in Prachuap Khiri Khan about 10pm on Sunday, reports the Bangkok Post.
He was wanted under an arrest warrant issued by the Phetchaburi Criminal Court, and charged with murder and concealing a body.
During a re-enactment on Monday (June 10), Anuwat told police he had met Benjarat through a dating app and had developed a serious relationship with her since the Songkran festival in April.
He took a flight from Bangkok to Phuket to meet her and she had picked him up from his hotel in a car. They had then gone to Prachuap Khiri Khan to collect a pickup truck they planned to return to her former boyfriend in Bangkok.
As they were passing through Sam Roi Yot district of Prachuap Khiri Khan on June 3, Mr Anuwat answered a phone call from his wife. When Benjarat found out he was not single, she had shouted at him and slapped his face, Anuwat said. He became furious and strangled her.
According to police, Anuwat said he then drove around looking for a place to dump the body, which he eventually did on the side of the highway in Khao Yoi district of Phetchaburi.