Stephen Violet, 19, of 1 Underhill Road, Sandy Hook, was arrested on a warrant charging him with first-degree robbery, police said.
In the robbery, two men armed with handguns burst into the Citgo gas station on South Main Street at 10:30 p.m. on a Friday, Jan. 20, police said.
Related story: Two men with handguns rob Newtown gas station
They stole cash from the register, and no injuries were reported, police said.
Violet has been in the custody of the Department of Correction since his arrest in Norwalk on Jan. 23 and was in the department's custody at the time of his arrest in the Newtown case.
He was held on $75,000 bond in this case.
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The Newtown armed robbery remains under investigation and other suspects were still being sought, police said.
"This was great police work both, by both the Norwalk Police Department and the Detectives' Unit from the Newtown Police Department, who worked in cooperation, in putting this case together, that led to this suspect, Stephen Violet, being arrested," said Newtown police spokesman Lt. Aaron Bahamonde.
Related story: Two More Men Facing Charges In January Armed Robberies In Norwalk
In January, Violet was one of four young men arrested in Norwalk after they were found in a car with marijuana and guns, police said.
In the case, Violet was arrested and charged with theft of a firearm, interfering with an officer, possession of drug paraphernalia, possession of less than four ounces of marijuana, possession of a controlled substance, carrying a gun without a permit, and weapons in a motor vehicle.
In March, Violet was arrested on additional charges in connection with three January armed robberies in Norwalk, police said.
He was arrested on three charges each of first-degree robbery and first degree conspiracy to commit robbery. He's also charged with first-degree threatening and six larceny charges. He was held on $225,000 bond in that case.
The arrest was in connection with robberies at Shorehaven Mobil gas station, Rainbow News & Variety and Brothers J&M grocery store in Norwalk. Three others face charges in those robberies as well.
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