Police on Thursday found what were believed to the severed hands of an 18-year-old girl who was allegedly killed by her boyfriend earlier this week.

Her body was found dumped beneath an elevated expressway in Pathum Thani on Wednesday.

The severed hands were found in a plastic bag near the Chiang Rak canal, about 4 kilometres from where the body was found, police said.

Found along with the hands were a lock of hair, women’s clothes, towels, snacks and baby wipes, police said.

Thanakorn Eiamlaor, 18, the suspected murderer, was detained on Wednesday after the victim’s body was found.

The suspect confessed to dumping the hands and a team of officers and rescue workers were able to find them.

The father of the suspect told police his son had been on drugs prescribed to him for mental illness since two years ago.

The suspect was detained at a housing estate while trying to overdose by swallowing many pills, police said.

The body of the victim, identified as Ranya Saensuriwong, 18, was found wrapped in a bedsheet, bound by three black belts.

The body had slash wounds to the neck and both her hands had been cut off.