The attack stopped only when a Good Samaritan stepped in.
Police are searching for the attacker and the Good Samaritan.
In the blink of an eye, a female clerk is punched in the face so hard that it sent her flying flat on her back.
It happened at the Multimex Services store on Sunday. They sell cellphones and offer other phone services. They also have security cameras fixed on just about every angle of the store. On one you can see the suspect at the counter.
"He was there for 15 minutes looking around, waiting for it to empty so he could make his move," said Detective Joe Camacho, of the Dover Police Department.
But while this was happening, the guy in the hoodie walks in. A customer who ends up being in the right place at the right time, after he buys something he turns to leave, but stops briefly to read an ad. At the same time back at the counter, the suspect makes his move.
"He punches her in the face, knocks her to the ground, tries to get behind the counter," Det. Camacho said.
That customer becomes a Good Samaritan, running back, and flipping a counter over on the robber.
"They had a real quick encounter, he interrupted, scared him away," Det. Camacho said.
The suspect is still on the loose, but police are also looking for that Good Samaritan hoping he can help again. Help them capture a man who would do this.
They're hoping he sees this story and comes forward, and that anyone else who recognizes the suspect will too.
"Immigration status does not matter, not what you may have done, we are a safe haven, we'd appreciate you help," Det. Camacho said.