A sheriff's deputy was shot and killed Saturday after responding to reports of gunfire at a trailer park in western Ohio, the sheriff said.
A second law enforcement officer also was shot at the Enon Beach trailer park in suburban Springfield.
His condition is serious, but he is expected to live, said Clark County Sheriff Gene Kelly.
Video from CNN affiliate WDTN shows the officer being shot. He falls to the ground and rolls before other officers help him to get out of the line of fire.
The unidentified suspect was shot and killed, said Kelly.
"This is the worst day in my 24 years as the sheriff of Clark County," Kelly said, his voice breaking with emotion. "It's a terrible tragedy for this community."
He declined to identify the deputy until he can notify her family.
"Our deputy never had the opportunity to return fire or take cover," said Kelly.
She had responded to reports of shots in the area and had begun her initial investigation when she was killed, he said.
Additional officers arrived on scene. As they approached, the suspect opened fire again and a gunbattle ensued, during which the second officer was injured, Kelly said.
He praised the fallen officer as an outstanding deputy. She was married and the mother of two children, he said.