An Australian man charged with murdering a Thai teenager and dumping her body in a suitcase has delivered a video message to her grieving family.

Simon Peter Carman, 46, from Ballarat, was arrested at Bangkok’s international airport allegedly attempting to flee Thailand on a Jetstar flight to Perth on Friday evening.

In footage recorded by police, Carman expressed regret to the girl’s family while also denying he killed the 17-year-old.

The victim (left) with her father and stepmother. Photo: Supplied

The victim has been identified as Tunchanok Donhomla, nicknamed ‘Cake’, who was an only child who lived with her father and stepmother.

“I feel bad for what happened to your daughter — it was out of my control,” Carman said to the camera.

“It shouldn’t happen. Please tell other girls just to be careful.”

The girl’s body was found stuffed in a suitcase by railroad tracks in the sex tourism and resort town of Pattaya.

Thai police found a suitcase near railway tracks. Photo: X

Carman denied involvement initially, according to The Pattaya News, but later claimed to have acted in self-defence when the teenager allegedly threatened him with a kitchen knife, reportedly during an argument over $20.

Thai media said Carman and Tunchanok met in Pattaya and had agreed on a payment of 1,000 baht ($43). They went to his condo but argued after he offered 500 baht instead ($20).

The ABC reported that police confirmed they had argued about money.

Police allegedly Simon Carman picked up Tunchanok Donhomla from the Beach Road vice strip in Pattaya. Photo: Pattaya police

The girl’s family said they had not stopped crying. Thai media reports they are demanding the death penalty.

In a media report, the victim’s stepmother, Oradee Bussarakum, stated: “I told the police I want him executed. As a stepmother I don’t know what else to say. I just want him executed.’’

Oradee said her stepdaughter went to Pattaya on June 16 for a holiday with her friend.

“She asked for money from her grandmother and she gave her some,” Oradee told the ABC.

“She said she wanted to see the sea.”

CCTV video shows an Australian man with a Thai girl who has died.

CCTV footage published by local media shows the girl and the Australian man entering a residential complex in the early hours of June 25.

Camera footage also appears to show the man leaving the residential building alone later that night, with a large black suitcase, and driving away with it on a motorbike.

The accused was on CCTV wheeling a suitcase from his building.

Police later found the suitcase near a railway roughly 4km away, media reported.

The naked body of the teenager was found inside and she had injuries consistent with an assault.

Video footage of the Australian shows visible scratch marks on his neck and arms.

The Department of Foreign Affairs and Trade confirmed it was providing consular assistance to an Australian detained in Thailand.

-with AAP