Florida man accused of killing girlfriend's 1-year-old son

TAMPA, Fla. - Police say they've arrested a 24-year-old man who is accused of killing his girlfriend's 1-year-old son at a Tampa motel.

Austin Hamilton is charged with the first-degree murder of Sincere Williams. His mother told police she left the boy and his 6-year-old sibling with Hamilton on Saturday while she went to work.

Hamilton called 911 after the child began having trouble breathing. The boy was pronounced dead at a hospital.

Police say Hamilton told them the boy urinated as he was changing his diaper. Hamilton said he "lost control" and hit the boy with a leather belt. He says he tried to pick the boy up, but the child fell and hit his head.

The Tampa Bay Times reports a medical examiner ruled the 1-year-old died from blunt-force trauma to the lower abdomen. The older child wasn't injured.

Hamilton is being held without bail.