A man has been charged after allegedly jumping out a bathroom stall and stabbing a man in the neck at a bar early Sunday in the North Side Wrigleyville neighborhood.

Gregg Greaves, 23, of the 4700 Block of North Beacon Street, was charged with one felony count of aggravated battery causing great bodily harm, police said.

Police responded about 12:30 a.m. to the Red Ivy sports bar in the 3500 block of North Clark Street, police said.

The suspect jumped out of a bathroom stall and stabbed a man in the neck with a broken beer bottle, police said. The man was also cut in the chin, hands and neck while fighting off the suspect.

Another man, who walked into the bathroom and saw the attack, helped to subdue the suspect until officers arrived, police said.

The man was treated and released from Advocate Illinois Masonic Medical Center, police said.

The suspect allegedly refused to wear pants and screamed obscenities at officers, police said. While being processed at the police station, the man defecated into his hands and flung the fecal matter onto the floor.

Greaves is due Monday in bond court.

© Copyright 2012 Sun-Times Media, LLC