New Jersey law enforcement was joined by local and federal officials in the investigation of the "suspicious letters." A letter addressed to former New York Mayor Rudy Giuliani that contained white powder was delivered to his Manhattan office, CNN said.
The unidentified white powder was sent in letters to three hotels in Lyndhurst, two hotels in Carlstadt and one in East Rutherford, where the NFL championship game will be played at MetLife Stadium.
East Rutherford Mayor James Cassella said the substance in one letter sent to the Homewood Suites was determined to contain cornstarch, CNN reported.
A New York Police spokesman said the white powder in the letter sent to Giuliani's office contained a "non-toxic substance."
Hazardous material units were sent to the Renaissance Meadowlands Hotel in Rutherford, the Hilton in Hasbrouck Heights, the Courtyard at Marriott and the Quality Inn in Lyndhurst, and an Econo Lodge in Carlstadt, the (Bergen, N.J.) Record reported.
Evacuations were not ordered at any of the hotels but guests on upper floors of the Renaissance were told to stay their rooms, the newspaper said.
Guests and employees in the lobby were moved to warm hotel shuttle buses and other vehicles.
"Preliminary tests indicate the substance was cornstarch," said Rutherford Police Chief John Russo.