OPD: Casey's robbed by masked man

OMAHA, Neb. -- The Omaha Police Department is investigating a robbery that happened at a gas station Sunday. 

Omaha Police were called to a robbery at the Casey's gas station at 2223 S 24th St. around 8:15 p.m.

Officers said when they arrived, they spoke with the store clerk who stated there was an unknown male in a ski mask who approached the counter, displayed a handgun and demanded cash from the register. 

Police said the suspect was last seen walking east on Martha St. 

This is an ongoing investigation.