Hazardous materials teams and a bomb squad were dispatched to five hotels near MetLife Stadium this morning after a suspicious white powder was discovered. County officials tested the substance and discovered that it was cornstarch in preliminary tests, according to NorthJersey.com, a local New Jersey media outlet.

Authorities were notified about the letters this morning when they received notification at 11:42 a.m., according to Jeanne Barratta, chief of staff to Bergen County Executive Kathleen Donovan, who was quoted in the NorthJersey.com article. At that time Barratta was unaware of anyone who had been exposed to the unknown substance. Authorities were dispatched to an Econo Lodge, a Homestead Inn, and a Renaissance Inn in East Rutherford, and a Holiday Inn Express and Hampton Inn in Carlstadt to investigate.

After testing one letter’s contents, officials determined that the powder was cornstarch. However, the FBI is monitoring the situation and CNN reports that law enforcement officials said the incident was considered a routine investigation, not a threat.

Additionally, authorities are looking into a similar matter in New York City as an envelope containing white powder was mailed to former New York City Mayor Rudy Giuliani, according to CNN. The substance was tested and authorities said it contained a “non-toxic substance,” but eight employees and the mailroom were decontaminated as a precaution.

Federal and local authorities have heightened security in the area surrounding MetLife Stadium as the NFL prepares for the Super Bowl this Sunday. Early estimates say that more than 80,000 people will flock to the area to see the Denver Broncos compete against the Seattle Seahawks.