A paramedic and the motorcyclist he was trying to help after a wreck were killed as a car drove into the scene of police, firefighters and others responding to the crash on a South Carolina highway Tuesday night, a sheriff said.

Four people in all were struck, including a state trooper and a Florence police officer, Florence County Sheriff TJ Joye said.

The first responders were helping after two motorcyclists were severely injured in a crash around 9 p.m. on state Highway 51 near Florence, The officers and paramedics had little time to respond as the car came toward them, the sheriff said.

"The city police officer pushed the trooper out of the way," the sheriff said. The police officer appeared to suffer a broken ankle and the trooper suffered a head injury, but both are expected to recover, Joye said.

The driver who hit the people was taken to a hospital. Investigators said she appeared to be elderly. The sheriff didn’t release her name or condition.

"Why she plowed through there, I have no idea," Joye said.

Florence County Coroner Keith von Lutcken confirmed the deaths Wednesday morning and said more details would be released later.

A crash reconstruction team out of Myrtle Beach is helping his department’s investigation. Deputies will review the team's findings and consult with prosecutors to see if any charges should be filed, the sheriff said.

Florence County Emergency Medical Services said its people are "heartbroken and overwhelmed by grief" by the deaths in a post on the agency's Facebook page.