According to the OSHP, a 2020 Ford F-150 was driving south on U.S. 127 when it went left of center and crashed head-on into a 2011 Chevrolet Impala.
The drivers of both vehicles suffered injuries.
Pamela Dull, 70, of New Madison, suffered life-threatening injuries and was flown to Reid Health in Indiana by a medical helicopter, OSHP said. Dull was later transferred to Miami Valley Hospital.
Eric Halderman, 22, of Camden, who was driving the pickup, was transported to Preble County Hospital with non-life-threatening injuries.
U.S. 127 was closed in both directions from U.S. 40 to Banta Road as of 3 p.m. but has since reopened.