DETROIT (AP) - Detroit's mayor says police Chief Ralph Godbee has stepped down after an internal affairs officer revealed the chief had been in a sexual relationship with a subordinate.

Mayor Dave Bing announced Monday morning that the 44-year-old Godbee submitted a letter of retirement, effective immediately, from the job he's held since 2010.

Bing placed him on a 30-day suspension last week pending an investigation into the claims by 37-year-old Angelica Robinson's attorney that she wanted the relationship to end and Godbee did not.

Godbee has not publicly commented on the claims.

At the news conference, Bing said assistant Chief Chester Logan will serve as interim chief. Logan had assumed Godbee's responsibilities during the suspension.

Bing said a national search for a new chief for the department is planned.

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