Mayor Eric Adams on Monday said he is considering three types of metal detectors to be used in the subway system in the wake of last week's mass shooting on board a Manhattan-bound N train in Sunset Park.

In his first in-person news conference since exiting COVID isolation, Adams offered few details on the added cost to the detectors, who will monitor them and where in the system they will be installed. He said he is delegating the task of researching the best type of detector to Phil Banks, deputy mayor for public safety.

At the news conference, Adams called the technology extremely promising, but he would not disclose the names of the manufacturers being formally reviewed.

“We’re looking at three devices. We haven’t narrowed in on just one yet,” Adams said. “Once we know we’ll make that announcement.”

Last week, the mayor’s office confirmed to Gothamist that Massachusetts-based Evolv Technology was under consideration. The company has developed an advanced detector capable of determining the density and shape alongside its metal composition, allowing their scanners to distinguish guns and bombs from some everyday objects like cellphones.

The detector then takes a photo of the person in question and tries to pinpoint where they’re carrying the metal object. Those images can then be used by a security officer to identify the carrier of a firearm.

Several city institutions are using Evolv detectors, including Lincoln Center, NewYork-Presbyterian Hospital and the American Museum of Natural History. The detectors were also installed at the Museum of Modern Art, the scene of last month’s stabbing of two employees there.

The mayor initially broached the idea of using metal detectors last week following the subway shooting in Sunset Park, where 10 people were shot and 13 people were injured.

Spokespeople for Gov. Kathy Hochul and MTA Chair Janno Lieber did not return emails seeking comment about Adams’ press conference.

Lieber did, however, say last week that he is open to considering any technology that’s demonstrated to improve safety. But Lieber said Sunday that he would also support the return of random bag checks.

Evolv Technology scanners during a voluntary run in the Los Angeles County Metro rail system in August 2017.

“On the bag checks, look, to their credit, the NYPD has been doing this since 9/11. So, they know how to do it,” Lieber told WABC-7's Up Close with Bill Ritter. “All I'm saying is let's take advantage of that know-how and put those bag-checks where the most people are.”

The use of metal detectors within New York City’s vast subway system is not new. In 2018, the NYPD installed a metal detector at the Port Authority as part of a pilot program to combat any terror attacks.

At the time of the 2018 program’s rollout, Donna Lieberman, executive director of the New York Civil Liberties Union, said the installation of metal detectors in subways will only “impart an illusion of safety and security at the very high cost of freedom.” Lieberman told Gothamist on Friday that advanced detectors would also fail to address the underlying issues behind crime, such as access to social services, mental health and the economy.

Subway systems across the country have embraced different methods of detecting weapons entering the system. In 2018, the Los Angeles rail system in partnership with the Transportation Security Administration introduced portable body scanners that were also developed by Evolv Technology. A year later, the subway system in Washington, D.C. introduced a similar pilot program.

At Monday’s news conference, the mayor said the detectors won’t be obtrusive and will simply add a layer of security.

"New Yorkers are going to feel safe knowing that when they swipe their MetroCards that we're doing some type of check to make sure people are not carrying weapons on our system,” Adams said, saying the city wouldn’t quietly install the detectors.