N.Y. Defense Emergency Act 1951 Law § 85
Any peace officer or any person employed as watchman, guard or in a supervisory capacity on premises posted in accordance with the provisions of section eighty-three of this act may stop any person found on any premises so posted and may detain him for the purpose of demanding, and may demand, of him his name, address and reason for being in such place. If such peace officer or employee has reason to believe from the answers of the person so interrogated or from his behavior or other attendant facts or circumstances that such person does not have permission to be in such place, such peace officer may forthwith arrest such person without a warrant on the charge of violating the provisions of such section or such employee may forthwith turn him over to a peace officer, who may arrest him without a warrant on the charge of violating the provisions of such section.
N.Y. Defense Emergency Act 1951 Law § 85