Matthew Clark, Greg Malandrucco Offer Reward For Information In Alleged Police Beating

03/25/2011 01:23 pm ET | Updated Jan 22, 2016

Two graduate students at the University of Chicago are looking for help in solving a ruthless beating they suffered, allegedly at the hands of plainclothes police officers.

Matthew Clark and Greg Malandrucco were having a late-night bite at Arturo's, a 24-hour taco restaurant in Chicago's Bucktown neighborhood, one night in February of last year. According to a lawsuit filed by the two men against the Chicago Police Department, Malandrucco accidentally bumped into a man while putting on his coat.

That man and a companion, both allegedly cops, then followed the two out of the restaurant and confronted them in a parking lot. They proceeded to savagely beat Clark and Malandrucco, leaving one unconscious and both in need of serious medical attention.

A squad car arrived on the scene, but rather than stopping the attackers, the lawsuit states that the officers joined in on the beating, "switch[ing] places with the plainclothes officer who was on top of Malandrucco, holding him down and striking him in the process." Surveillance video appears to lend credence to that story.

More than a year later, Malandrucco tells CBS that the city is refusing to reveal the identities of the officers they claim were involved in the incident. To help them move their case forward, they have posted new, wide-angle surveillance footage in addition to the closer footage that was already available, and they've made audio of their 911 call public as well.

That call is almost immediately interrupted by a shouting voice, which Clark and Malandrucco claims belongs to one of the officers, who then punched Clark in the face to keep him from finishing the call.

The two victims have also set up a toll-free tip line at (800) 621-3908, and are offering a $10,000 reward to anyone who can identify the officers in question, according to a separate CBS report.