A teenager went into a hotel room holding hands. Hours later, her body was found in a suitcase.

Thai police arrested a Ballarat man at the airport with fresh scratches after a 17-year-old girl was found dead by a railway.

A young girl trusts a stranger, steps into an elevator, and never walks out. It is a parent's worst nightmare, and it just unfolded in a busy Thai resort town.

WHAT HAPPENED

Police in Thailand arrested a 46-year-old Australian man on Friday night. They stopped him at Bangkok's main airport as he tried to board a plane.

Officers say they found the body of 17-year-old Tunchanok Donhomla earlier that evening. She was folded inside a black suitcase dumped near a railway line in Pattaya.

Security cameras show the two walking into a hotel room together on Thursday morning. The man left alone hours later with a heavy suitcase strapped to his motorcycle.

What the evidence shows

• CCTV shows the pair holding hands at 3:30 a.m. on Thursday.
• The man left the hotel alone at 9:30 p.m. with a 26-inch black suitcase.
• The victim's body was found in that same suitcase near a railway line.
• The 46-year-old suspect had deep scratch marks on his arms and neck when arrested.
• Police say the hotel room showed clear signs of a violent struggle.

THE BIGGER QUESTION

This tragedy shines a light on a dark corner of tourism. Pattaya is famous for its nightlife, but it can be highly dangerous for young local women.

How do we protect young people from wealthy older tourists? We must ask why a child was in a position to meet a stranger on a nightlife strip in the middle of the night.

THE OTHER SIDE

The suspect has not yet given a public statement or entered a formal plea in court. His defense team will likely question the CCTV timeline and ask if anyone else could have entered the room.

However, the fresh scratches on his body and the clear camera footage make this a very tough case for his defense.

WHAT HAPPENS NOW

The Australian man remains in Thai custody facing murder charges. He will likely face a trial under the Thai legal system rather than being sent back to Australia.

For the family of Tunchanok Donhomla, they are left to plan a funeral for a life cut short far too soon.

WHAT WE STILL DON'T KNOW

Why was a 17-year-old girl out on the Pattaya nightlife strip at 3:00 a.m.?

• Did the suspect have a history of violence in Australia or Thailand?
• What was the exact cause of death according to the autopsy?