Thai police say a local man has been arrested on suspicion of raping and killing a German tourist on the island of Koh Si Chang in the Gulf of Thailand.

Thai police said the victim was approached and attacked by Ronnakorn Romruen, a native of the small island, while she was traveling on her rental motorbike.

Ronnakorn was tracked down and arrested on Monday through a series of CCTV images.

Police say the suspect, who operates a trash collecting boat, admitted to the crimes and said he used drugs before the incident.

The body of the 27-year-old tourist with injuries on head and legs was found Sunday hidden under rocks and a pile of leaves.

Koh Si Chang is a popular weekend destination for both locals and foreigners.