Police in the suburbs of New York City made the first arrest under a new local law banning face masks, officials announced Tuesday.

Nassau County Police say officers on Sunday night responded to reports of a suspicious person on a street near the Levittown and Hicksville town line, about 30 miles (48 kilometers) east of Manhattan.

They found Wesslin Omar Ramirez Castillo wearing black clothing and a black ski mask that covered his face, except for his eyes.

The department said the 18-year-old resident displayed other suspicious behavior, including attempting to conceal a large bulge in his waistband and refusing to comply with the officers’ commands.

Officers say the bulge turned out to be a 14-inch knife. Ramirez Castillo was placed under arrest without further incident, police said.

He was arraigned Monday in Family Court in Westbury on misdemeanor charges of criminal possession of a weapon and obstructing governmental administration, according to Nassau County District Attorney Anne Donnelly’s office.

Lt. Scott Skrynecki, a police department spokesperson, said Ramirez Castillo will also be facing a misdemeanor violation of the face mask law in the coming days.

Nassau County Executive Bruce Blakeman, a Republican who signed the mask ban into law earlier this month, said Sunday’s arrest showed the rule is working.

“Our police officers were able to use the mask ban legislation as well as other factors to stop and interrogate an individual who was carrying a weapon with the intent to engage in a robbery,” he said in an emailed statement. “Passing this law gave police another tool to stop this dangerous criminal.”

Keith Ross, a criminal justice professor at the John Jay College of Criminal Justice in New York City, said police didn’t necessarily need the new law to stop and question Ramirez Castillo, but it helped bolster their justification.

“The law gives police, at the very least, reasonable suspicion to conduct a stop,” the retired New York City police officer explained by phone. “Under reasonable suspicion, police can forcibly stop a person in New York state if they are suspected of committing a felony or a penal law misdemeanor, which is where this new law falls.”

But Scott Banks, attorney-in chief at the Legal Aid Society of Nassau County, which is representing Ramirez Castillo, challenged that notion.

“There is no basis to believe that wearing a face mask was intended to conceal identity or criminal behavior, and if that was the basis of the stop I believe there is a basis to conclude the stop was unlawful,” he wrote in an email.

Skrynecki declined to comment, adding that police and county officials will discuss the incident at a news conference Wednesday.

The New York Civil Liberties Union, which has criticized the new law, repeated its warning that the mask ban is “ripe for selective enforcement by a police department with a history of aggression and discrimination.”

Disability Rights of New York, a group that advocates for people with disabilities, filed a legal challenge last week arguing that the mask law is unconstitutional and discriminates against people with disabilities.

The federal class action lawsuit seeks a temporary restraining order and preliminary injunction to immediately stop enforcement of the ban.

The Mask Transparency Act was approved by the county’s Republican-controlled legislature in response to “antisemitic incidents, often perpetrated by those in masks” since the Oct. 7 start of the Israel-Hamas war.

The law makes it a misdemeanor punishable by up to a year in jail and a $1,000 fine for anyone in Nassau to wear a face covering to hide their identity in public. It exempts people who wear masks “for health, safety, religious or cultural purposes, or for the peaceful celebration of a holiday or similar religious or cultural event for which masks or facial coverings are customarily worn.”

(AP)