It happened at the Shell gas station off Northside Drive and 14th Street early Monday.
The clerk told WSB-TV′s Darryn Moore a man charged at his co-worker with the butter knife. But what makes this case so strange is how the man got to the clerks.
Police said he slipped through the hole in a bulletproof window to attack.
“He came in immediately and started screaming and shouting and jumped. He was very, very scary,” Berhan Nemaneta said.
Both Nemaneta and his co-worker ran out of the store and locked the man inside until police could arrive.
The other clerk received some minor cuts to his head but is going to be OK.
Police have not identified the man and are working to figure out a motive behind the attack. The owner may release video of the attack later today.