SALT LAKE CITY (AP) — Federal prosecutors in Utah have charged a man accused of sexually abusing a 3-year-old boy on a plane.

Investigators say in court documents filed Tuesday that the child was seated next to Kevin C. Matthews on the flight from Chicago to San Diego with a layover in Salt Lake City.

Charging documents say that the boy’s mother was concerned about being seated across the aisle from her son Monday, but their family was flying standby and Matthews appeared to be friendly.

Prosecutors say other passengers saw Matthews touch the child inappropriately after the boy fell asleep and reported the groping to flight attendants, who moved the child to his mother’s lap.

The Deseret News reports Matthews is 48 and from Illinois.

Defense attorney Susanne Gustin did not immediately return a message seeking comment.

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