A blood-covered madman with two knives rampaged through Manhattan in a savage broad daylight stabbing spree that left two men dead and a woman clinging to life Monday, police said.

The sick suspected stabber — a mentally ill homeless man with eight previous arrests in New York City alone — was stopped by a heroic officer thanks to the help of good Samaritans, including a taxi driver and a British tourist, said NYPD Chief of Detectives Joe Kenny. and police resources.

Ramon Rivera, 51, was identified by sources as the person of interest in custody, seen with a long beard and coarse hair in a gray mugshot obtained by The Post. Police have no other suspects in the wave of “unprovoked” random attacks, Mayor Eric Adams said during a morning briefing.

“Today we have three innocent New Yorkers, just going about their lives, who have been victims of a terrible, terrible attack,” he said. “It’s a clear, stark example of the criminal justice system and the mental health system continuing to fail New Yorkers.”

Surveillance footage obtained by The Post shows a bearded man matching Rivera’s description sticking a long knife in the pocket of his sweatshirt as he stood outside a building on West 19th Street in Chelsea — about 20 minutes before authorities say police was his first strike in the deadly attack.

The hours-long rampage stretched from Chelsea and Crosstown to the East River and left a 36-year-old construction worker and a 68-year-old man dead, Kenny said.

The third victim — a 36-year-old woman — was stabbed multiple times and remained in critical condition Monday, he said.

Police were still piecing together the movements of the crazed stabber, but it appears he walked at least part of the way during the blood-soaked rampage that spanned both the west and east sides of Manhattan .

The bloody attacks broke out around 8:20 a.m. when the suspect walked up to the construction worker in front of 444 West 19th Street in Chelsea and stabbed him in the stomach, police said.

The construction worker was rushed to Bellevue Hospital, where he died, police said.

A blood-stained blue towel was left on the sidewalk where the victim collapsed, hours after the senseless attack took place.

The screams of a woman pushing a stroller alerted a doorman to the stabbing. The doorman told The Post that he narrowly missed seeing the suspect running away.

‘She had a small child. She was hysterical,” the doorman said.

“The construction worker was stabbed 3 meters in front of her. She saw him stabbed twice with a kitchen knife.”

The sinister perpetrator fled south on Ninth Avenue, police said.

About two hours passed before the violent threat moved to 500 East 30th Street, near FDR Drive and The Water Club, where the 68-year-old man was fishing in the East River, Kenny said.

The crazed attacker stabbed the fisherman several times before running away, Kenny said.

The victim was also taken to Bellevue Hospital, where he also succumbed to his injuries, the chief said.

Hours later, police could be seen packing the unfortunate fisherman’s fishing rod into evidence.

The third and final stabbing took place in the shadow of the United Nations building at East 42nd Street and First Avenue, Kenny said.

The 36-year-old woman was stabbed multiple times in full view of several witnesses, Kenny and sources said.

After the stabbing, a pool of blood and a trail of blood remained on the ground.

An ambulance rushed the seriously injured woman to Weill Cornell Medical Center, while several good Samaritans contacted police, sources said.

A British tourist and UN diplomatic security personnel who witnessed the stabbing helped track down the suspect, sources told The Post.

A taxi driver who also watched the attack and believed it was a robbery followed the stabbing and alerted Officer Robert Garvey, who caught up with the suspect at 46th Street and First Avenue near the Turkish mission to the U.N., Kenny said.

“When (Officer Garvey) was alerted that this perpetrator might be involved in a crime, thinking it might be a robbery, he detained him, and at this point obviously information comes over the radio, the detectives become involved ,” Kenny said. “We’re starting to put the pieces together and realize it’s part of the three attacks that have happened (as of) this morning.

“At this stage these attacks appear to have been unprovoked, that he simply walked up to them and started attacking them with the knives.”

“Had Officer Garvey not been there, this individual would likely have continued these random acts of violence,” Adams added. “So he saved the lives of fellow New Yorkers.”

The suspect — Rivera, according to sources — had two large kitchen knives covered in blood, Kenny said.

His clothes were also soaked in blood, raising the real possibility that he walked through Manhattan and randomly targeted innocent New Yorkers, the chief said.

“From the video we’re seeing now, we have a video of him with the knives out,” he said.

“But at this time our investigation is preliminary. It appears he was traveling on foot.”

Rivera, a homeless resident of the Bellevue Men’s Shelter, had a long trail of recent arrests and two mental health incidents in which police responded, sources said. He also had an extensive history of arrests from several other states, sources said.

The clashes with the NYPD left Rivera behind bars for much of this year. He was released from Rikers Island only a month before the attacks, sources said.

Rivera’s criminal record includes five burglary arrests dating back to December 2023, along with a petty theft collar that month, mostly in Manhattan, sources said.

He was also arrested in May for assaulting a corrections officer at the Bellevue Hospital Psychiatric Center, sources said.

In October, Rivera was arrested on grand larceny charges after prosecutors said he stole an acrylic bowl worth nearly $1,500 from a store in Tribeca, sources said.

Court records show he pleaded not guilty and was released on bail with non-monetary conditions.

He also pleaded guilty to charges of burglary and assault in three separate cases in recent months, for which he received prison time, sources said.

Adams said it’s unclear why the suspect was back on the streets, calling it a systemic failure.

“There are some real questions we need to look at, why he was on the streets, and he has some serious mental health issues that should have been explored, and that’s what we want to find out in the investigation,” Adams said.

The charges against the suspect were pending Monday evening.

Additional reporting by Reuven Fenton