Hermiston police are now offering a $500 reward for information leading to the arrest and conviction of the suspect.
The attempted robbery occurred at 10:15 a.m. Saturday at Tienda la Comadre.
“Nothing was taken from inside the store, but we are treating this as an active investigation for the attempted robbery,” said Chief Jason Edmiston.
The suspect, who was wearing dark clothes, including a hooded sweatshirt, gloves and something covering his face, was in the store for only about 5 seconds before running out, Edmiston said.
The 6-foot-tall suspect also had a dark backpack and a weapon that resembled a handgun.
Edmiston said investigators don’t know if the weapon was a real firearm, but they are considering the suspect to be extremely dangerous.