CHICAGO (CBS) — Shots were fired Thursday afternoon outside Portillo’s South Loop location, according to the FBI.

The FBI said agents who happened to be getting lunch in the South Loop, were driving into the Portillo’s parking lot, in the 500 block of West Taylor Street, when they heard gunshots. WBBM’s Steve Miller reports.

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An agent got out of his vehicle and detained one person with a handgun, until Chicago Police arrived to make the arrest.

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The FBI said three agents were on the spot at Taylor and Canal by chance.

“Right place and right time. Yes, sir,” said Garrett Croon, FBI Spokesman. “At approximately 12 noon, three FBI agents were in the parking lot of Portillo’s and overheard gunshots. One of the FBI agents exited his vehicle and detained a male in the parking lot and discovered that male had a handgun on him.”

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He said agents did not fire any shots. No injuries were reported.