Man on Scooter Shoots People Seemingly at Random in New York, Kills One, Injures 3

The seemingly random attacks in Brooklyn and Queens started at 11:10 a.m., police said, and officially ended exactly two hours later with a suspect arrested in the latter borough, police said, NBC News reported.

The man, identified only as a 25-year-old with a prior arrest, had a 9 mm semiautomatic handgun with an extended magazine and an "illegal" scooter without plates, New York Police First Deputy Commissioner Edward Caban said at a news conference.

The suspect has not been responsive to detectives and appears to suffer from emotional or mental issues, police sources said. It's not clear if he's been evaluated by a mental health professional, however.

The victim of the first attack was described as a 21-year-old man shot from behind in Brooklyn and expected to survive, Assistant Chief Joseph Kenny said at the news conference.

Seventeen minutes later an 87-year-old man was shot in the back roughly three miles away, in Queens, police said. He was rushed to a hospital where he died, they said.

"The perpetrator was described as a male on a scooter firing at a nail salon on Jamaica Avenue," Kenny said.

At nearly the same location, but in a separate attack, a shot was fired, but no one was struck, police said. "Numerous witnesses described the male on a scooter randomly firing at a group of people that was standing on the corner," the assistant chief said.

Less than a mile away, also in Queens, a 44-year-old man standing on a street corner was shot in the face, police said. He was hospitalized in critical condition.

A few blocks away, at 11:37 a.m., the final victim known to police, described as a 63-year-old man, was shot in a shoulder, police said. He was stabilized at a hospital, they said.

Four shell casings were found at that scene, they said. Other scenes also presented multiple 9 mm shell casings, they said.

A blurry security camera image of a suspect on a scooter was sent to "every cop in the street," Kenny said.

NBC New York reported that the image was sent out to officers as part of a system that will sound an alarm on their devices until they acknowledge having seen it.

At 1:10 p.m., roughly 10 blocks from the last attack, the 25-year-old suspect was taken into custody by officers who recognized him from the security image, police said.

It wasn't clear what the suspect had been doing in the more than 90 minutes that passed since the last shooting.

Caban said detectives are investigating the origin of the firearm and the possibility it's a ghost gun, a term that describes weapons that can be 3D printed from composite material and put into use without required serial numbers or customary background checks.

The biggest mystery seemed to be motive.

"At this time, we don't know the motive," Kenny said. "It seems that it's actually random if you look at the demographics and pedigree of the victims. They're all different at this time."

The nonprofit Everytown, which urges evidence-based gun regulation, states that random shootings are likely less common than believed: The attacker in nearly half of all mass shootings in the United States is a partner, ex-partner, or relative of one of the victims.

Everytown defines a mass shooting as one in which four or more people are killed. The Gun Violence Archive, which tracks mass shootings in the United States, defines a mass shooting as one with four victims, not including the shooter, who are injured or killed by gunfire.

It counts New York's violence Saturday morning as a mass shooting. There have been more than 360 mass shootings under that definition since the beginning of the year, according to the archive.