The incident came just days after flames ravaged Notre Dame Cathedral in Paris.
The 37-year-old New Jersey man had pulled up on Wednesday night in a minivan outside the cathedral on Fifth Avenue in Manhattan, walked around the area, then returned to his vehicle and retrieved the petrol and lighter fluid, according to the New York Police Department.
Deputy commissioner of intelligence and counter-terrorism John Miller said: "As he enters the cathedral he's confronted by a cathedral security officer who asks him where he's going and informs him he can't proceed into the cathedral carrying these things. It's at that point some gasoline apparently spills out onto the floor as he's turned around."
Security then notified officers from the counter-terrorism bureau who were standing outside, Mr Miller said. The officers caught up to the man and arrested him after he was questioned.
Around 7:55pm, a man walked into St. Patrick's Cathedral in Manhattan with gas cans and lighter fluid, and was subsequently apprehended by @NYPDCT without incident. We thank our partners for their help, and remember - if you see something, say something. pic.twitter.com/qEbmklnqzQ— NYPD NEWS (@NYPDnews) April 18, 2019
"His basic story was he was cutting through the cathedral to get to Madison Avenue. That his car had run out of gas," Mr Miller said. "We took a look at the vehicle. It was not out of gas and at that point he was taken into custody."
We are investigating an incident at St. Patrick's Cathedral. Expect a heavy police presence.— NYPD Midtown North (@NYPDMTN) April 18, 2019
Update to follow.
"It's hard to say exactly what his intentions were, but I think the totality of circumstances of an individual walking into an iconic location like St Patrick's Cathedral carrying over four gallons of gasoline, two bottles of lighter fluid and lighters is something that we would have great concern over. His story is not consistent."
Mr Miller said the suspect is known to police, who are currently looking into his background.
St Patrick's Cathedral was built in 1878 and has installed a sprinkler-like system during recent renovations.
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