Leavenworth ? Leavenworth police arrested a 22-year-old man on suspicion of killing his 2-year-old son.

Maj. Patrick Kitchens, a police spokesman, said the man was arrested about 4 p.m. Friday, about an hour before the boy died. His name has not been released, pending formal charges, and police also declined to release the child’s name.

Police expected to present the case to prosecutors Monday, Kitchens said.

Officers responded Thursday night to a report of a child falling. They found the boy unconscious and severely injured. The child’s mother was not present, Kitchens said.

The toddler was flown to Children’s Mercy Hospital in Kansas City, Mo., where he died.

“Up until that point, we were investigating this as a child-abuse case,” Kitchens said.

An autopsy was scheduled for Saturday.