ANTIOCH (CBS SF/BCN) – After watching a drug buy at an Antioch shopping center Sunday night, an alert police officer arrested a man who had an automatic handgun.

Antioch police said an officer was on patrol at the Sycamore Square shopping center when he observed the drug buy and approached the suspect, according to an 11:59 p.m. post on Facebook from the Antioch Police Department.

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The man fled on foot and ran along nearby railroad tracks. The officer pursued, caught and arrested the 39-year-old man, whose identity was not released.

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A gun, drugs and cash seized during an arrest in Antioch on Sunday, Jan. 2, 2022 (Courtesy of Antioch Police Department)

The officer found the man in possession of an automatic handgun, and a large amount of cash, marijuana, cocaine and other drugs.

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