MINNEAPOLIS - Prosecutors have charged a predatory offender with criminal sexual assault after investigators linked him to three similar assaults on the same night.

Stephen Lee Blanks, age 32, is charged with aggravated robbery and criminal sexual assault in connection with one of the cases. Additional charges are pending.

Minneapolis Police were dispatched on January 3 to an apartment building on the 1600 block of 6th Street South on an unknown trouble call. When they arrived they found a 79-year-old woman on a gurney being moved into an ambulance. The woman said she was returning to her 6th floor apartment after retrieving her mail when a man came up behind her, put his hand over her mouth and dragged her away from her apartment and into a stairwell.

The elderly woman told investigators the man punched her in the face multiple times, hit her head against the stairwell wall, then pulled her undergarments down and attempted to have sex with her. Other residents came running when the woman screamed and they were able to get a good look at the suspect before he fled.

While investigating that attack detectives became aware of two strikingly similar assaults that took place nearby within minutes. Surveillance footage from these attacks matched the description of the suspect in the first sexual assault. Both involved a physical attack and attempted sexual penetration.

Prosecutors say hours after the multiple attacks Banks turned himself in to the Hennepin County Jail on an unrelated warrant. He was wearing clothing identified by witnesses to the attacks, and investigators were able to identify Banks as the same man seen on surveillance footage from the attack scenes.

The criminal complaint filed in the case says Banks is a convicted predatory offender who is required to register with the State of Minnesota for the rest of his life.