Harinder Bains, the owner of a bar in Linden found Ahmad Khan Rahami sleeping in the doorway of his bar on Monday.
Bains said he was watching news on TV on his laptop from another business across the street.
At first, he thought he was some "drunk guy" resting in the vestibule, but then recognised Rahami and called police.
"I am just a regular citizen doing what every citizen should do. Cops are the real heroes, law enforcement are the real heroes," Bains told.
When officers responded, Rahami pulled out a handgun and opened fire, striking an officer in the chest.
A foot chase ensued, during which Rahami shot at a police car, causing a bullet to graze another office in the face.
The chase ended when Rahami was shot multiple times.
He was taken to a hospital for surgery. Rahami was not initially cooperative with police who tried to interview him, a law enforcement official said.
Indian-American attorney Ravi Batra said that Bains "dared to honour his Oath of Citizenship to protect & defend the Constitution from enemies foreign and domestic -- and it turns out that the Chelsea Pressure Cooker Bomber suspect, a naturalised citizen, is caught by another immigrant, an Indian-American Hero-Sikh."
In a statement, the National Sikh Campaign said this was brave and courageous act by Bains.
"A Sikh helps police get to the terrorist involved in New York and New Jersey bombing over the weekend," it said.
"He heroically helped save many innocent lives and yet gave credit to law enforcement officers. Harinder Bains certainly did what every responsible citizen in America ought to do. Brave and courageous act!" said the National Sikh Campaign.
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