Emergency crews were at the scene of an injury accident on Ohio 13 near Baseline Road, the Richland-Huron county line.
A pregnant woman who was riding in a horse-drawn buggy involved in the crash was taken to a hospital by emergency medical helicopter. Three other people had minor injuries, according to an official at the scene.
According to a press release from the Mansfield post of the Ohio Highway Patrol, the crash happened at 10:59 a.m. on Ohio 13 south of Baseline Road in Butler Township.
Gary Polachek, 39, of Greenwich, was southbound on Ohio 13 in a white 2005 Ford truck. Norman Brubaker, 32, of Greenwich was southbound on Ohio 13 in a horse-drawn black Amish buggy.
The buggy also was occupied by Wilma Brubaker, 31, and two children ages 5 and 2. Polachek struck the buggy in the rear, pushing it into the ditch, according to the patrol.
Norman Brubaker and the two children were taken to OhioHealth Mansfield Hospital, where they were treated for minor, non-life-threatening injuries.
Wilma Brubaker, who is pregnant, was taken to MetroHealth Medical Center in Cleveland, where she is in stable condition. Polachek was not injured.
The horse was not injured, investigators said at the scene.
The crash remains under investigation, and Ohio 13 was closed for approximately one hour, according to the patrol.