The New York City police department plans to pilot the unmanned aircrafts in response to complaints about large gatherings, including private events, over Labor Day weekend, officials announced Thursday.

“If a caller states there’s a large crowd, a large party in a backyard, we’re going to be utilizing our assets to go up and go check on the party,” Kaz Daughtry, the assistant NYPD Commissioner, said at a press conference.

The plan drew immediate backlash from privacy and civil liberties advocates, raising questions about whether such drone use violated existing laws for police surveillance.

“It’s a troubling announcement and it flies in the face of the POST Act,” said Daniel Schwarz, a privacy and technology strategist at the New York Civil Liberties Union, referring to a 2020 city law that requires the NYPD to disclose its surveillance tactics. “Deploying drones in this way is a sci-fi inspired scenario.”