Two passengers stepping off a disabled Greyhound bus were hit by a car early Friday along Interstate 70. One was killed and the other was seriously injured, the State Highway Patrol said.

The bus was headed from New York to St. Louis when the driver pulled over on an interstate ramp around 3:45 a.m. because of mechanical problems.

The driver warned passengers to stay on board while he placed reflective safety triangles behind the bus, but some people got off to take a smoke break, said Eric Wesley, a spokesman for Greyhound Lines, Inc.

It was dark outside, and two of those passengers wandered onto the ramp, said Lt. Tony Bradshaw, a patrol spokesman. The car's driver, Eddie McElfresh, 27, swerved to try to avoid a collision and struck them both, he said. The crash was under investigation.

The passengers' identities were not immediately released, pending notification of their families. Bradshaw said the survivor was flown to Ohio State University Medical Center in Columbus with injuries that didn't appear to be life-threatening.