CCTV footage captured Ms Tunchanok and Mr Carman walking from the Pattaya beachfront, a well-known area frequented by sex workers, and entering the foyer of his accommodation together at approximately 3.30am on Thursday, June 26.
Several hours later, Mr Carman was allegedly seen on camera leaving the building alone with the large black suitcase, which he transported by motorbike.
Police allege he folded the teenager’s naked body into the 29-inch suitcase and dumped it in long grass beside the railway tracks, approximately 4.2 kilometres from the property, before attempting to leave the country.
Officers arrested him at Suvarnabhumi Airport minutes before his Jetstar flight JQ76 to Perth was scheduled to depart.
Investigators located the suitcase with Ms Tunchanok inside.
Along with her body, police found the white Onitsuka trainers she had been wearing that night, jeans, underwear, a mobile phone case, a wallet, and her gold bracelet and necklace.
Tattoos on her back, arms, chest and left leg were confirmed to match those in her social media images.