Durham police went back to the scene of a rape after a threatening letter was found there, NBC 17 News reported on Thursday.

Police are investigating whether or not the rapist and the person who left the note are the same person.

The roommate of the rape victim said she found the letter taped to her front door at the Forest Pointe Apartments in Durham.

"It shouldn't be like this," the roommate said. "It said, 'I'm watching you [expletive]' and it was left in red ink. They're trying to send me a message."

The note comes just 24 hours after a masked man armed with a box cutter forced his way into an apartment and raped a 19-year-old woman.