An officer was bruised but OK on Saturday after his ballistic vest stopped a bullet during a Friday night exchange of gunfire with a man who is still at large, Nicholasville police said.

Officer John Rainey, who has been with the department 16 years, suffered severe bruising in the back where he was struck, said Nicholasville police Sgt. Scott Harvey.

"The vest stopped the round. The vest did its job," Harvey said.

Rainey was treated at St. Joseph Jessamine in Nicholasville for "pretty severe bruising," and he was then released, Harvey said.

"It's a really hard hit, as you can imagine," he said.

Police said it was unclear whether the suspect was hit by Rainey's fire. Shortly after 8 p.m. Friday, Rainey saw a man duck between two houses on Maple Leaf Drive, Harvey said.

Rainey got out of his cruiser and went behind a house where he had seen the man. The man fired several shots, and one struck Rainey in the back of his bullet-resistant vest, Harvey said. Rainey returned fire.

Other officers searched the area with help from a Lexington police helicopter.

The only description police have of the man is that he wore dark-colored clothing. Anyone with information is asked to call Nicholasville police at (859) 887-5447.

Greg Kocher: (859) 231-3305. Twitter: @HLpublicsafety