The suspect is still on the loose, but police hope not for long. They released a apicture of the suspect Thursday afternoon taken from that surveillance video.
Police say the assault happened around 10 p.m. Wednesday night when a woman in her 20s was entering the building while talking on a cell phone. Police say the suspect grabbed her, told her he had a knife and threatened to kill her.
The man forced the woman into the building. The on-duty guard apparently thought they were together. Police say the suspect then forced the victim through a door into the alley and assaulted her.
Some residents say they heard the attack took place in the building's garbage room.
"You would have to live here to know where it is. Because when I first saw this place, when they walked me around, I couldn't find the trash room," said Jason Weglarz, Hyde Park resident.
"Unfortunately, women, especially if you're out at night, have to be very, very careful. Any neighborhood, in any situation," said Robert Mason, Southeast Chicago Commission.
Mason says that although there is a 24-hour security detail guarding barack obama's house a few blocks away, incidents like this can happen anywhere. Residents of the building, however, say they feel that it's safe.
"We take the bus to class when we come in, I'm with someone, my roommate usually and we say that's one of the reasons we chose to live here," said Fri Awasun, Hyde Park resident.
The suspect also made off with the victim's purse and keys.
If you have any information about this incident you're asked to call police.