Northern Kentucky police departments are investigating three similar convenience-store robberies from late last week.

"Based on everything we know about each of these three crimes, we think it's probably the same suspect," said Casey Kilgore, a Fort Thomas police detective.

The Citgo gas station on Royal Drive in Fort Mitchell was robbed at 1 a.m. July 15. Fort Mitchell police were called after a man with a gun entered and demanded money, then fled with about $90.

The store's video camera shows the robber as a white male, about 5-foot-4, wearing an oversized gray and blue hooded sweatshirt and a scarf. He carried a large, black frame pistol with a wooden grip, witnesses told police.

At 2:30 p.m. July 16, the BP gas station at the corner of Highland and Grand avenues in Fort Thomas was robbed at gunpoint by a man in a blue hooded sweatshirt, Kilgore said. The robber stole $350 from the station, he said.

Kilgore said a BP in Florence also was robbed last week and that the Florence, Fort Mitchell and Fort Thomas police departments are working together.