An American college student and musician studying in the Netherlands was stabbed to death by a man believed to be her roommate, Rotterdam police said.

Sarah Papenheim, 21, of Minnesota, was found in her Rotterdam apartment Wednesday. Police said in a statement that attempts to revive her were unsuccessful.

Authorities arrested a 23-year-old man, who they said knew Papenheim, shortly after the attack at a train station in Eindhoven. His name has not yet been released.

The victim's mother, Donee Odegard, told NBC-affiliate KARE 11 that the man police arrested was her daughter's roommate.

Sarah Papenheim via Facebook

Odegard said that her daughter was studying psychology at Erasmus University. She said Papenheim took an interest in psychology after her brother died by suicide in 2015.

"She can't help everybody, but she thought she could," Odegard said, adding that her daughter was also trying to help her roommate.

"She just thought that she was at least there for him, and I don't know what he thought differently," Odegard said.

Odegard told The Star Tribune that her daughter was scheduled to return home this month after she booked a gig with a local musician.

“My only two kids, and I’ve lost them both,” Odegard said.

Police are working to determine a motive for the crime. Investigators said there was an argument in the apartment before the stabbing.

The suspect made his first court appearance Friday and was ordered to remain behind bars for two weeks while police investigate.