The first happened just before 8:30 p.m. in Washington Heights at the 168th Street station on the A-C-E line.
Police say a 24-year-old man was standing in the mezzanine when two teens tried to rob him. They stabbed him and ran away.
The man refused medical attention and is expected to survive.
RELATED | Man stabbed inside Kew Gardens, Queens subway station during attempted robbery
Then a half hour later, just before 9 p.m., a 31-year-old man was riding on a southbound train in Morningside Heights when he saw another man smoking on the train.
He asked the man smoking to move and was stabbed in his arm with a knife.
Mayor Eric Adams and Governor Kathy Hochul recently unveiled their plan to combat crime and homelessness on the subway.
The NYPD will enforce the MTA's code of conduct: like no sleeping on trains or carrying piles of trash and possessions.
Police will once again issue summons.
Charlton D'Souza, with a volunteer group called United Pasengers has been patrolling the subway stations through the city, and is eagerly waiting to see how Mayor Adams' plan works.
"Let's give it three weeks, and let's see how it works out," he said.
TOP NEWS | NAACP calls for officers in viral NJ mall fight video to be disciplined
Mental health professionals will join cops on patrol.
Homeless outreach teams will be sent out to the highest-need stations like Grand Central Terminal, Penn Station and Times Square.
"Eric was a transit police lieutenant when I was chief of transit police in 1990," former NYPD Commissioner Bill Bratton said on Up Close. "In 1990-1991 we cleaned up the mess in the subway with 5,000 in that system, several hundred living in the tunnels. Rampant fare evasion and disorder and we kept it straight for 28 years."
So far, no arrests have been made in any of the four violent subway crimes.
* Get Eyewitness News Delivered
* More Manhattan news
* Send us a news tip
* Download the abc7NY app for breaking news alerts
* Follow us on YouTube
Submit a News Tip