He waited until the Pembroke Pines gas station convenience store was empty before asking the cashier to use the bathroom.
When he came out, police said he walked behind the counter, pulled out a gun and demanded cash from the register.
The entire robbery, at the Chevron at 10255 Pines Blvd., was captured on store surveillance cameras.
Police are hoping the video of Tuesday’s robbery will help identify the man, who detectives say “is likely the same suspect that is responsible for a series of similar robberies throughout Miami-Dade and Broward counties.”
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The clip shows the man, who was wearing a black baseball hat, a black shirt with a picture of a dog on the front, black shorts, and black shoes, walk up behind the clerk, pull a gun from his waistband and point at the register.
According to the incident report, the clerk handed over the cash, but the robber wasn’t happy.
The clerk told the officer that robber said: “That’s it? Where are all the 100 dollar bills?”
After being told that the manager is the only one with the key to the safe, the robber took off, police said.
He is being described as being 25 years old with a slim build.
Anyone with information is asked to call Pembroke Pines Investigations Division at 954-431-2225 or Broward Crime Stoppers at 954-493-TIPS (8477).