An out-of-town woman visiting her boyfriend in Arlington told police early Sunday that she woke in the middle of the night to find another man having sex with her.

Federico Alfonso Umana Barrera, 35, of Arlington, has been charged with sexual assault and forgery of a public document, according to police. Bail has not been set and he remained in jail Monday afternoon, according to the Arlington County Sheriff's Office.

The woman and her boyfriend, who lives in the 300 block of North Oxford Street in Ashton Heights, went out to dinner Saturday night and drank alcohol, police spokesman Dustin Sternbeck said.

When they returned home, they saw several neighbors, including Barrera, having a cookout, drinking and hanging out. They joined in. The woman knew Barrera from past visits to Arlington, Sternbeck said.

The couple later returned to the boyfriend's apartment and they fell asleep together on his couch, Sternbeck said.

The woman told police she later woke up to find Barrera having sex with her. At first, she thought it was her boyfriend; upon realizing who it was, she told the man to get off of her, Sternbeck said.

The woman told police she tried to get her boyfriend's attention, which caused Barrera to flee, Sternbeck said.

Once he was gone, the woman was able to wake her boyfriend and they called police.

Sternback did not have information on the forgery charge.

This investigation remains ongoing, Sternbeck said.