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NYPD commissioner: Still unclear whether terror suspect acted alone

04:12

Joining TODAY live, James O’Neill, commissioner of the New York Police Department, says that Sayfullo Saipov, the suspect in Tuesday’s terror attack, is being questioned, and it’s still unclear whether “he acted alone or had help.” He urges New Yorkers to be alert for suspicious activity. He says that despite President Trump’s criticism of the justice system, in New York City, “the justice system is not a joke.”