At least four people were stabbed on New York City’s subway platforms and trains on Saturday, and another person was killed while walking on the tracks, amid a chaotic 24-hour period for the transit system.

The string of violence came one day after Mayor Eric Adams and Governor Kathy Hochul announced a new subway safety plan aimed at bringing hesitant riders back onto trains by increasing the presence of police and introducing more mental health professionals.

But the ensuing disorder on Saturday highlighted ongoing challenges that authorities will face in improving public perception of the transit system, which has seen an uptick in some violent crimes in the last year.

As of Sunday afternoon, the four separate stabbing incidents had not yielded any arrests, according to the NYPD.

Among the victims was a 20-year-old woman who was punched in the back and then stabbed three times in the abdomen while standing on a platform at the Livonia and Van Siclen Avenue station in Brooklyn just before 3 p.m. on Saturday, police said.

Authorities could not say if the attack was random or if the two individuals knew each other. The victim was hospitalized with non-life-threatening injuries.

Later in the evening, two more stabbings were reported within an hour in Upper Manhattan. According to police, a 24-year-old man was stabbed in the leg during an attempted robbery in the mezzanine of the 1 train at 168th Street in Washington Heights at around 8:20 p.m.

Just before 9 p.m., another man was slashed in the arm while riding a southbound 1 train at 116th Street. An NYPD spokesperson said it was unknown if the incidents were related.

Police were also searching for a suspect accused of stabbing a homeless man in the buttocks and the eye at the Jamaica-Van Wyck subway station on Saturday. The attack occurred around 3 a.m. on Saturday morning, after three men approached the victim and demanded he turn over his belongings.

“The subways are the lifeblood of our city. The mayor has been crystal clear that for a full recovery to happen, our subways must be safe and the Subway Safety Plan begins that work,” Fabian Levy, a spokesperson for Eric Adams, said in a statement.

He cautioned New Yorkers against conflating random acts of violence with the issue of subway homelessness that the mayor’s new plan is primarily intent on solving. “While the mayor strongly condemns yesterday's attacks and has made clear that violence of any kind is unacceptable, we need to understand the root cause of each matter to stop the violence,” Levy added.

Aaron Donovan, an MTA spokesperson, noted that the new subway plan had not officially started, but was slated to begin on Monday.

"Investigations into Saturday’s incidents are in early stages, but these events underscore the urgent need for the initiative that Governor Hochul and Mayor Adams announced last week to enhance services for people with serious mental illness experiencing homelessness, and to step up enforcement of the code of conduct in the subway system," Donovan said.

Also on Saturday night, a man was fatally struck by a 3 train while reportedly walking on the tracks near 50th Street in Manhattan, according to the MTA. Additional information about the victim was not immediately available.

At a recent MTA board meeting, MTA Chairman Janno Lieber warned that high-profile incidents, including subway shoving and track trespassing incidents, had unsettled riders, despite an overall downward trend in transit crime.

Read More: Straphangers speak out a month after fatal subway shoving

According to NYPD data, while some categories of transit crime have fallen, others, including murders, rapes and assaults, were all on the rise in the last year. The system saw 461 felony assaults last year, the highest total since 1997, and an increase of 25% from 2019, despite the pandemic-fueled decrease in ridership.

In his subway safety plan on Friday, Adams said that police would take a heavier hand in cracking down on disorder in the transit system.

“No more smoking, no more doing drugs, no more sleeping, no more doing barbecues on the subway system,” Adams said. “No more just doing whatever you want. No, those days are over.”

As part of the new plan, the mayor said that homeless people would be forced to leave the system at the end of the line, drawing sharp rebuke from homeless advocates who accused the mayor of “dehumanizing rhetoric.”