Big Island police said they are investigating a robbery that happened Friday night at the Shell service station on Kuakini Highway in Kailua, Kona.

An unidentified man armed with a handgun entered the gas station's convenience store with his face obscured and demanded money. He then fled the area on foot and headed southeast toward Kopiko Plaza with an undisclosed amount of cash.

He is described as Caucasian, possibly in his 20s, about 6-feet tall, slim and wearing a black hooded sweatshirt and blue jeans.

Police ask anyone with information about this case to call Detective Sean Smith at 808-326-4646, ext. 275, or the Police Department's nonemergency line at 808-935-3311. Tipsters who prefer to remain anonymous may call CrimeStoppers at 808-961-8300 in Hilo or 808-329-8181 in Kona.