A murder charge has been filed in the weekend death of a Detroit police officer who was shot while pursuing a crime suspect.

Sgt. Ken Steil died Saturday, five days after the shooting. Marquise Cromer had been charged with attempted murder, but the charge was changed to first-degree murder Monday.

The 21-year-old Cromer will appear in court Tuesday. His attorney, Sanford Schulman, wasn't immediately available for comment.

Prosecutor Kym Worthy says, "We will aggressively ensure that justice is done."

Police say Steil was shot in the shoulder a week ago while pursuing Cromer, who was wanted for shooting his father. Steil was expected to survive but developed complications Saturday.

Forty-six-year-old Steil was a 20-year veteran of the Detroit department and nicknamed "Shark" for his diving skills.