Murder charges are being brought against an ex-convict who allegedly shot and killed a police officer at Wayne State University.

Officer Collin Rose, who graduated from Ferris State's criminal justice program, was killed earlier this week while trying to arrest 31-year-old DeAngelo Davis.

Officials say Davis was riding a bicycle when Rose stopped him and was shot shortly after requesting help from other officers.

Davis is being charged with first-degree murder, murder of a police officer, and gun crimes.

Rose is the only Wayne State officer ever killed in the line of duty.