New York City truck attack terrorist Sayfullo Saipov was interviewed by Federal investigators about potential terrorist ties all the way back in 2015.

The Department of Homeland Security Investigations Unit believed Saipov was familiar with two men who had recently been entered into the country’s terrorist database but didn’t have enough evidence to pursue him.

Saipov’s name and address was listed as a “point of contact” for two different men whose names were entered into the Counterterrorism and Criminal Exploitation Unit’s list after they came to the United States from “threat countries,” one federal official told ABC News.

One of the two men has vanished and is being actively sought by federal agents as a “suspected terrorist.”

Saipov, 29, came to the United States from Uzbekistan through a Diversity Visa Program lottery in 2010, making him a legal permanent resident of the United States upon arrival. He has lived in Ohio, Florida and, most recently, Paterson, N.J., where federal agents interviewed Saipov in 2015.

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