Police in Detroit have a mystery on their hands: Where are the parents of two toddlers who were found alone in a motel that had a bullet hole in a window?

Police were called to the Cranbrook Motel near 8 Mile Road in Detroit after there were reports of people arguing and then gunfire. A man, who was walking through the motel's parking lot was wounded, WDIV reported.

>> Read more trending news

The man was listed in serious condition, WJBK reported.

But as police investigated the reports, they found a bullet hole in one room’s window and two children, both under the age of 2, alone inside the room.

One of the children was in a crib. The other was found on a bed. Both had dirty diapers, but were otherwise unharmed, WXYZ reported.

Child Protective Services has custody of the children until the parents can be found, WJBK reported.