Four people, including one child, were taken to hospitals following a two-vehicle crash at county roads 57 and 9 near Bellefontaine.
Three medical helicopters were called to the scene to transport those who were injured.
A vehicle with two adults and one child traveling east on CR 57 failed to yield at a stop sign and struck an eastbound vehicle on CR 9, according to the Ohio Highway Patrol Marysville Post.
Crews were dispatched after the crash was reported at 8:15 a.m., according to the Logan County Sheriff's Office.
The identities of those involved were not released and their conditions injured were not available.