The 51-year-old suspect, identified as Ramon Rivera, was charged with three counts first-degree murder as a serial killer after being taken into police custody on Monday.
He was found with blood on his clothes, and is believed to be homeless and a resident of the Bellevue men's shelter on East 30th Street.
It all unfolded when a 36-year-old construction worker, Angel Lata Landi, was fatally stabbed at 444 West 19th Street just before 8:30 a.m. He was pronounced dead at Bellevue Hospital.
Then, a 67-year-old man fishing was stabbed at 500 East 30th Street just before 10:30 a.m. He was also pronounced dead at Bellevue Hospital.
Officials say the suspect then traveled north where a 36-year-old woman was stabbed near the U.N. at East 42nd Street and First Avenue at 10:55 a.m. Police said the suspect stole her purse. She was taken to New York Presbyterian Hospital in critical condition, and later died due to her injuries.
An Uber driver witnessed the third attack, and followed Rivera up First Avenue, calling out the window to pedestrians to help.
"I'm walking with him, I'm saying 'drop it man, it's not worth it,'" said witness Baha Biten. "I told him 'drop the bag, there's going to be cops up ahead.'"
Veteran NYPD Officer Robert Garvey was there.
"Just heard a commotion, stepped outside, heard what people are saying and reacted," Garvey said.
He stopped Rivera, dumped out his bag and found not one, but two knives. One of them was slick with blood. He was taken into custody at East 46th Street and First Avenue.
"If Officer Garvey was not there, these random acts of violence, this person conceivably would have continued those random acts of violence. So, he saved the lives of fellow New Yorkers," Adams said.
Surveillance video obtained by Eyewitness News shows the man putting on a hoodie, skullcap, and gloves, then pulling out a giant knife from his backpack, hiding it in his shirt before walking away.
Detectives are attempting to determine the connection between the stabbings and what motivated the attack.
He appeared to pick his victims at random.
"He just walked up to them and began to attack them with the knives," Chief of Detective Joe Kenny said.
The suspect has eight prior arrests and Mayor Eric Adams said "There's a real question as to why he was on the street."
The suspect is believed to have severe mental health challenges, the mayor said.
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