NEW YORK (CBSNewYork) – After a series of recent slashing incidents on New York City subways, the Guardian Angels returned to the subway system.

Founder Curtis Sliwa boarded the uptown No. 1 train Monday with several colleagues in response to a series of subway attacks, 1010 WINS’ Juliet Papa reported.

Sliwa said there will be regular day and night patrols on the subways for the first time since 1994.

“We’ve decided to not only be out during the day, which we haven’t been, but also ramp up our efforts at night to try to stop these slashing,” Sliwa said.

There have been at least six slashings in less than a month.

The most recent incident took place Sunday morning at the Central Park North 2 train platform. A man and a woman were arguing when the woman asked a stranger for help. The stranger then slashed the victim in the face.

No arrests have been made.

Last week, a man attacked a 71-year-old woman on a D train pulling into the Broadway-Lafayette station and a 29-year-old woman was slashed on the hand on a No. 3 train in separate incidents.