A subway rider made a citizen’s arrest of a violent straphanger who repeatedly kicked a passenger on a Brooklyn subway train and hurled a racial slur at the woman.

Anna Lushchinskaya, 40, was charged with felony assault following the wild Tuesday morning incident around 8 a.m. aboard the D-train in Sunset Park, the NYPD said.

The 24-year-old woman targeted by Lushchinskaya had boarded the northbound train at the 9th Avenue-39th Street stop — and Lushchinskaya launched the attack that left the victim bleeding with cuts to her face, police said.

In two videos posted to Twitter by another rider — who appeared to detain Lushchinskaya on the 36th Street station platform until the cops showed up — the suspect can be seen unleashing the rage-filled assault.

“F—k off! F—k off! Fuck off!” Lushchinskaya shouts to a silent woman who is standing next to her and appears to be preoccupied with her phone, one of the clips posted by Juan Ayala under the Twitter handle @ PlatanoMan shows.

Lushchinskaya appears to hit the woman’s hand.

The maniacal, blonde-haired woman is then seen taking off her sunglasses, putting her hair up in a ponytail, and pulling an umbrella out of her bag.

Suddenly, out of nowhere, Lushchinskaya kicks the woman, prompting fellow straphangers to intervene.

“They’re not letting me hit her back!” shouts Lushchinskaya who then calls a man “f—king retarded” for trying to stop her.

The woman who Lushchinskaya attacked then tells her: “You come touch me I will punch you right back. I don’t care who the f—k you are.”

Then Lushchinskaya whacks the woman with her umbrella and repeatedly kicks her as the woman kicks her back.

At some point, according to cops, Lushchinskaya hit the victim with keys.

When Lushchinskaya continues to hit the woman with her umbrella, the video shows, the man filming the clip says: “It’s too early for this sh-t…she’s not even fighting you back, bitch.”

Straphangers keep trying to stop the raging woman — who shouts “f—k off” — with one rider saying, “Lady, obviously you have problems.”

In a second video posted to Twitter, Lushchinskaya can be heard saying, “Don’t f—k with me you piece of sh-t,” before appearing to spit on the floor.

Lushchinskaya, who is white, then flips the bird to the Asian woman she beefed with and calls her a “f—king c–nk.”

That racial vitriol sparked gasps from riders, and prompted Ayala to shout: “What! What!…F—k out of here with that racist sh-t.”

In another video posted to Twitter by user @BlipintheCosmos, Ayala is seen confronting Lushchinskaya who then spits on the floor.

“Do not spit at me,” Ayala tells Lushchinskaya who then refers to him as “Mohamed.”

“Bitch, I’m Dominican,” Ayala says. “Did you just try to call me Muslim or some sh-t.”

Ayala then tells Lushchinskaya as he continues to film her that “the whole world is laughing at you,” before she rips his headphones out of his ears and smacks his phone out of his hand.

The video then shows Ayala forcibly grab Lushchinskaya and throw her on the ground as other straphangers yell for him to “stop” seconds before the video ends.

Ayala later posted a Twitter photo showing him holding the unruly woman on a subway platform with the caption: “Then she tried me so I had to detain her until the cops showed up.”

Another photo the man posted shows Lushchinskaya getting hauled away by police.

The NYPD Transit Twitter account announced Lushchinskaya’s arrest in a tweet saying, “Thank you to everyone who intervened and provided information.”

Ayala, 31, sustained minor injuries from the incident, police said.

Meanwhile, authorities say that on June 28, Lushchinskaya was involved in another subway incident on the same train.

In that case, Lushchinskaya allegedly sprayed an unknown liquid at a 36-year-old man on a northbound D train at the 36th Street stop, police said. She was charged with assault.