DENVER -- Denver police are investigating a home invasion involving a sorority house at the University of Denver.

Police said that around 5:45 a.m. Thursday a man entered the Gamma Phi Beta Sorority house at 2233 S. Josephine St. He entered two occupied rooms. One woman in one of the rooms woke up and said the man made a verbal threat to her before taking items and leaving, police said.

The only description police have is of a man wearing dark clothing.

"That's not good. That's really upsetting," said Hannah Moskowitz, a sorority sister.

One of the women pulled a building fire alarm and fire units arrived at the sorority house before police did.

Police are investigating to see if the break-in might be related to other burglaries in the neighborhood that happened during the winter and spring around the University of Denver.

"To say they are linked at this point in time, we are not comfortable with that," said Sonny Jackson, of the Denver Police Department. "But we will definitely look at it."

In March, Denver police released a composite sketch of a man suspected in 13 burglaries. The suspect has never been caught.

"It is scary because he had confrontations with a bunch of people and he hurt them," said Ashley Gaalema, who lives down the street from Gamme Phi Beta. "I can't go to sleep at night sometimes thinking that he might come into my apartment one night."

"With all the burglaries on the other side of campus, we have been really cautious, punching in the code making sure someone is not behind us, pulling the doors closed, making sure it's not propped open," said Danielle Chandler, of Delta Delta Delta.

The investigation into the connection continues.