DETROIT (AP) — Detroit police say two 18-year-old men have been arrested in the fatal shooting of an off-duty Detroit firefighter.

Capt. Michael McGinnis says a second suspect in the slaying of 29-year-old Jack Wiley Jr. was arrested Friday in Detroit, a day after the first arrest occurred in Dearborn. Neither of their names has been released.

McGinnis says the second man arrested is believed to have been an acquaintance of Wiley.

A motive for the slaying hasn't been released.

A relative found Wiley dead Tuesday in his Detroit house. His car had been stolen, but was recovered a few hours after police were called to the scene.

Wiley was the son of a firefighter and had been with the Detroit department for four years.