MILWAUKEE (CBS 58) -- Charges have been filed against a 22-year-old man accused of beating a 56-year-old man to death. 

Harry Bruce, who was a special education teacher at Roosevelt Middle School, was killed Thursday, Nov. 12, near 12th and Walnut streets in Milwaukee. Daylan Mallard has been charged with first degree intentional homicide in connection with his death. 

Milwaukee police say when they arrived at the scene shortly after 5:30 p.m., Mallard was standing in a grassy area by a bus stop with no clothing on except his underwear and socks. 

According to a criminal complaint, a witness told police while she was exiting a Milwaukee County Transit Bus (MCTS) she observed a man -- identified as Mallard -- severely beating on 56-year-old Bruce. She then called 911. The witness, per the complaint, says she saw Mallard put Bruce in a headlock, punch him 20-30 times, and observed Mallard drag the victim by a lanyard that was wrapped around his neck.

Investigators spoke with another witness, who stated he was at Speed Queen with his two friends for food when a woman approached them saying, "So y'all just gonna stand there and let him kill him?" 

According to the complaint, the group followed the woman to see what was going on. The complaint says the witness and his friends told Mallard to stop attacking the victim and pulled the lanyard away from him. 

Police then arrived and Mallard was taken into custody.