A lifelong New Yorker was ambushed on a busy sidewalk -- one of the victims in a what law enforcement sources describe as a series of "rock" assaults on people in the Morningside Heights.

In one particular incident, police say Nicole, a 47-year-old woman, was attacked Wednesday morning around 7:45 a.m. while jogging in Riverside Park.

According to the victim, she was entering the overpass in the park that starts around W 125 St. when a man came up from behind and hit her with a brick, rock, or another blunt object before fleeing.

The area is said to be a popular route for Columbia University students, runners and bikers.

"He was not agitated or seem angry and did not take my phone or valuables. And he didn’t run particularly fast after he hit me. Just a blank look on his face," Nicole told News 4 New York.

The woman says she had airpods on and didn't hear the attacker approach.

“I felt this excruciating pain at the top of my head like a brick or something had fallen on me. I almost saw stars like a cartoon, everything sort of went black," she said, adding that when she turned her head she came face-to-face with her attacker.

She describes the attacker as being of slight build and wearing a unique, almost retro, multicolored hoodie.

"It was this multicolored hoodie that was almost retro-looking and color blocked with oranges and reds and a little bit of a rainbow. It was unique and he had the hood up," Nicole said.

Covered in blood, students from Columbia University and passersby rushed over to help Nicole. They called 911 and waited for an ambulance. Nicole says she was taken by ambulance and treated at St Luke’s Hospital with staples to the head to close the wound.

Law enforcement sources confirm the aforementioned incident is part of a “rock incident assault” pattern. Nicole is at least the third victim in the last week who has been ambushed from 119th to 125th Streets near Riverside Park and hit on the head with a rock by possibly the same man, according to law enforcement sources.

“I love this city. Running is my happy place. I love this neighborhood and I was really concerned about this man being on the street and I was really concerned upon learning he’s a serial attacker," she said.

So Nicole decided to call News 4 New York to sound the alarm.

"This is our city and we have to keep each other safe. These are our parks and our streets and I feel like there should be more of a community effort," she said. "If something is perpetrated against the community they should know about it.”

Law enforcement sources tell News 4 New York that the NYPD is putting more officers in the area as the search for the attacker, or attackers, continues.