CHICAGO (CBS) — Chicago police have released surveillance images of a robber who pretended to be an undercover officer, punched a 70-year-old man in the face, and stole his wallet Tuesday morning at a subway stop in the Loop.

Police said around 2:45 a.m. at the Monroe stop on the Blue Line, a suspect approached a man on the platform, told the victim he was an undercover police officer, and demanded the man’s ID.

When the victim pulled out his wallet, the robber tried to snatch it. When the victim resisted, the robber punched him in the eye, and ran away with his wallet.

blue line robbery 1 Robber Posing As Undercover Officer Punches Man, Steals Wallet At Loop Subway Stop

Surveillance camera images of a robber who posed as an undercover police officer, punched a man in the face, and stole his wallet at the Monroe stop on the CTA Blue Line on March 6, 2018. (Credit: Chicago Police)

The victim was taken to Northwestern Memorial Hospital for minor injuries.

The robbery was caught on CTA surveillance cameras. Police said the robber was a black man who appeared to be a 50 to 55 years old, 6 feet to 6 feet 2 inches tall, and 180 to 220 pounds. He was last seen wearing a grey knit cap, black puffy coat, blue jeans, and tan boots. He also was carrying a black garment bag.

blue line robbery 2 Robber Posing As Undercover Officer Punches Man, Steals Wallet At Loop Subway Stop

Surveillance camera images of a robber who posed as an undercover police officer, punched a man in the face, and stole his wallet at the Monroe stop on the CTA Blue Line on March 6, 2018. (Credit: Chicago Police)

No one was in custody Tuesday afternoon.

Anyone with information about the robbery should call Area Central detectives at 312-747-8384, or submit an anonymous tip to tipsoft.com.

blue line robbery 3 Robber Posing As Undercover Officer Punches Man, Steals Wallet At Loop Subway Stop

Surveillance camera image of a robber who posed as an undercover police officer, punched a man in the face, and stole his wallet at the Monroe stop on the CTA Blue Line on March 6, 2018. (Credit: Chicago Police)

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