The robbery occurred at about 1:36 a.m. at 753 West 31st Street.
Store surveillance video shows the incident. It began with a seemingly standard order, with a man picking out a few items and a single employee behind the counter.
"He bought a bottle of orange-apple juice and a bag of chips. He put it on the counter," said owner Harry Patel.
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As he hands over cash or a card to pay, that's when the sale switches to a hold up.
"When the drawer opened up, that's when he pulled the gun on him. And that's when he took the money, and he left," said Patel.
You can see the employee's hands immediately go up, and the offender reaches over the counter and begins rifling in the cash drawer. At one point he picks up the register or a money bag, snags its entire contents, and runs off.
The Subway is just steps from the 9th District police station.
"I heard about this in other parts of the city earlier in the evening and here I am dealing with it," said Patel.
Police said the suspect fled the scene in an unknown direction. No one was injured and Area One detectives are investigating.
Chicago police said detectives are now stringing together at least seven other sandwich shop robberies across the city in the South Loop, River North and Near West Side over the past few days.
Those robberies occurred in the:
1200-block of South Canal Street on June 25, at 4:20 a.m.
700-block of South Western Avenue on June 26, at 11:47 a.m.
2500-block of West North Avenue on June 27, at 10:45 a.m.
700-block of North Milwaukee Avenue on June 30, at 9:00 a.m.
0-100-block of West Ohio Street on July 8, at 4:00 a.m.
1200-block of South Canal Street on July 15, at 3:45 a.m.
1600-block of West Roosevelt Road on July 16, at 10:28 p.m.
600-block of South Wabash Avenue on July 18, at 3:48 a.m.
Police released a photo of a man they believe may be the perpetrator of the series of robberies.
If you recognize the man or have any further information, contact Chicago police.
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