COLUMBIA – Authorities are investigating an armed robbery that occurred at the Columbia Mart located at 890 Lancaster Avenue in Columbia, Lancaster County. A white male entered the store on Wednesday, Nov. 15 at 10:06 p.m. and displayed a handgun demanding money. The man was wearing all black clothing with a camouflage mask. He was last observed walking across Route 462 towards Ninth Street. Photos of the suspect can be seen below. Anyone with information is asked to contact Columbia Borough Police at 717-684-7735.