Police in New York City are searching for a man suspected of slashing a woman on the hand after issuing a terrifying threat on board a subway train, marking the third such attack in 48 hours.

Police responded to a southbound 3 train at the Atlantic Avenue station in Brooklyn at around 9.30pm Tuesday after receiving a 911 call about an assault.

Officers who arrived on the scene found a 29-year-old woman suffering from a cut to her right hand.

Do YOU know this man? the NYPD are searching for this man, who is suspected of slashing a woman's hand on board a 3 train in Brooklyn Tuesday evening

Police say the suspect, described as a black man, about 5-foot-9, weighing 175lbs, approached another rider, told her, 'I will chop you up on this train,' and then sliced her hand with an object wrapped in cloth

The seemingly random attack took place as the 3 train was pulling into the Atlantic Avenue station in Brooklyn

Eight minutes after the 3 train assault, a 32-year-old man was slashed in the face while waiting for a 6 train at the 116th Street station in Harlem

The victim told police that a fellow subway rider approached her with the words, 'I will chop you up on this train,’ and then proceeded to strike her with an object wrapped in cloth. When the train came to a stop, the attacker fled.

The woman was taken to an area hospital to be treated for her injuries and was later released.

The NYPD has released CCTV screenshots showing the suspect in the attack, who was described as a black man, about 5 feet 9 inches tall, weighing 175lbs, with short black hair.

He was last seen wearing a black puffy jacket, green cap and green camo pants, and he was carrying a white backpack.

Just eight minutes after the attack on board the 3 train, a 32-year-old man was slashed in the face inside the 116th Street train station along the 6 line in East Harlem, reported New York Daily News.

The victim then walked to Harlem Hospital, where he received stitches and was released. Police said the man is not cooperating with the investigation.

The two incidents occurred just hours after a 21-year-old man was arrested for allegedly slashing a 71-year-old Brooklyn grandmother in the face inside a D train Monday.

There has been a string of seemingly random slasher attacks in New York City since the beginning of the year.

Damon Knowles was charged with assault with intent to cause disfigurement and serious physical injury in connection to the attack on Carmen Rivera, a mother-of-three and grandmother-of-nine.

Rivera was attacked on a southbound 6 train that was approaching the Bleecker Street station at around 7.15am Monday.

Damon Knowles, 21, was taken into custody late on Tuesday night suspected of slashing Carmen River, 71

Courageous: Carmen Rivera, a 71-year-old grandmother-of-nine, smiles as she returns to her home in the Bronx on Tuesday, one day after she was slashed by a stranger on her morning commute to work

Police released this artist's impression of the suspect and CCTV footage of the man leaving the subway

The NYPD said a male passenger sitting across from Rivera lashed out at her. Both the man and Rivera got off at the next stop.

Footage from inside the subway station shows the suspect jumping over the turnstile as he ran away.

Knowles reportedly became a suspect after he was charged with criminal trespass and resisting arrest in another incident on Tuesday, according to the Daily News.

Speaking outside her home on Tuesday, Rivera said she did not realize she had been cut until getting off the train.

She said the man fell on her as she was sitting, and somehow managed to hide the slashing and the blade.

Rivera needed 30 stitches to close the 4-inch cut on her left cheek.

However she insisted on returning to her job as a sample maker on Tuesday, and remains defiant about what happened to her.

Knowles, pictured, was arrested following Monday's attack on the 6 train which injured Carmen Rivera

'What's going to happen is going to happen. That's it,' she told CBS New York.

'I'm not afraid. I've never been afraid. I guess that is just me.'

'I take that train every morning.'

Family members said Rivera initially denied what happened to her, saying she had cut herself at work, before finally admitting that she was attacked.

The Monday attack was preceded by at least three other similar incidents involving slashings since the beginning of the new year.

Anthony Cristopher-Smith, 30, from Newark, New Jersey, was walking in the East village on January 19 when a man yelling profanities knocked him off his feet and slashed him in the face from his ear to his jawline.

Police later arrested Francis Salud, 28, in connection to the attack. Salud has also been charged for a similar attack on East 23rd Street in October.

Amanda Morris was viciously slashed in the face on her daily commute to work in Chelsea on January 6

Earlier incident: Anthony Christopher-Smith was walking down East 6th Street near Cooper Square with headphones on January 19 when he was knocked to the ground and slashed across the face

On New Year's Day, a 28-year-old woman suffered a facial wound at the hands of a total stranger in The Bronx, and less than a week later, 24-year-old Amanda Morris was sliced with a sharp object while walking to work in Chelsea.