DARKE COUNTY, Ohio -- Deputies in Darke County are investigating a three-vehicle collision that happened late Tuesday morning on Route 47 midway between Union City, Ohio and Ansonia.

A preliminary investigation revealed that a semi-tractor, driven by 54-year-old Andrezej Latacz, from Ontario, Canada, was eastbound on Route 47, attempting to pass an eastbound farm tractor, driven by 46-year-old John Grow, from Union City, when he struck a Head Start bus. The bus was driven by Candance Riegle, 64, of Ansonia, which was pulling onto Route 47 from a private drive.

The semi then struck the farm tractor, causing the tractor to overturn several times. Latacz and Grow were taken to Wayne Hospital in Greenville.

Deputies said there was one adult and three children on the bus. They were not injured.

The collision remains under investigation.