On a rush-hour metro train, a shooter wearing a gas mask and a construction vest detonated a smoke bomb and fired a hail of bullets.

Authorities have beefed up security for New York City Mayor Michael Bloomberg following the discovery of "concerning" social media remarks by a suspect in the Brooklyn subway massacre.

When police were attempting to locate the renter of a van suspected of being involved in the violence, they came across the posts made by someone with the same identity.

James Essig, Chief of Detectives, stated that investigators were unsure whether the guy named Frank R James, 62, was connected to the train attack.

The carnage began Tuesday when authorities said that a shooter wearing a gas mask and a construction vest detonated a smoke bomb and opened fire on a rush-hour subway train. At least ten people were shot.

Authorities stated that someone with the same identity as the van renter made social media statements about homelessness, New York, and Mayor Eric Adams.

According to Mr. Essig and Police Commissioner Keechant Sewell, the incident prompted officials to increase the mayor's security detail. She described the posts as "concerned."

The attack transformed the subway into a horror picture, with a smoke-filled vehicle firing at least 33 rounds of gunfire, authorities said. Fearful commuters fled the train while some limped off. On the platform, at least one person collapsed.

"My subway door sprang open into disaster. "There was smoke and blood and people screaming," eyewitness Sam Carcamo told 1010 WINS radio station.

The gunshots began as the train approached a station in the Sunset Park neighborhood, about a 15-minute ride from Manhattan and primarily populated by Hispanic and Asian residents.

Five people were listed as critical but were expected to survive. According to hospitals, at least 29 people were hospitalized in hospitals for gunshot wounds, smoke inhalation, and other illnesses.

Ms. Sewell stated that while the act is not being examined as terrorism, she is "not ruling anything out." The shooter's motivations remained unknown.

Mr. Essig said authorities discovered a nine-millimeter semi-automatic handgun, extended magazines, a hatchet, detonated and undetonated smoke grenades, a black rubbish can, a rolling cart, fuel, and the key to a U-Haul truck at the site.

He stated that the key assisted detectives in locating the van renter, who had residences in Philadelphia and Wisconsin.

According to police, detectives identified a person of interest when the credit card used to hire the van was discovered at the shooting scene.

The van was discovered abandoned elsewhere in Brooklyn.

According to police, investigators believe the weapon jammed, stopping the suspect from continuing to fire. The federal Bureau of Alcohol, Tobacco, FirearMs., and Explosives has concluded an urgent investigation to determine the firearm's manufacturer, seller, and initial owner.

The incident alarmed a community already on edge due to increased gun violence and the constant fear of terrorism. Some New Yorkers were fearful of riding the country's busiest subway system, and spurred officials to beef up security at transportation hubs from Philadelphia to Connecticut.

Last fall, the Metropolitan Transportation Authority stated that it had installed security cameras in all 472 subway stations throughout the city, claiming that they would expedite the prosecution of criminals. However, the cameras at the station where the train arrived did not appear operational.

Janno Lieber, the MTA's system chief, told television interviewers he had no idea why the cameras failed. However, he stated that police had "a variety of different options" from cameras located across the subway line to catch a view of the gunman.

A rider's video, recorded via a closed-door between subway vehicles, shows a person wearing a hooded sweatshirt extending an arm and pointing at something as five bangs are heard. Another video shows smoke and people pouring out of a subway car, several of whom are limping.