Gary Hershorn/Getty Images(NEW YORK) — New York City police are searching for the owner of a pit bull that attacked a woman on the subway during an altercation.

The incident, which reportedly occurred on Friday afternoon on the 4 train in Manhattan, was caught on video by a passenger riding the train.

Onlookers to the incident say the owner sat down and placed the dog in the seat next to him when it bumped into the woman in the next seat over. The woman asked the man to remove his dog, which escalated into an altercation between the two passengers, and the dog responded by latching onto the woman’s shoe.

The video, recorded by eyewitness TahSyi Kyng, shows the woman struggling to release her foot from the dog’s bite, while chaos ensues in the train car.

The owner was trying to pull the dog off the woman but “he never told the dog to let go,” Kyng told ABC News. The owner “never announced that it was a service dog,” and it did not appear to be one, though it was on a leash, Kyng added.

The woman freed herself by taking her foot out of the shoe, which the owner threw at her before exiting the train, according to Kyng.

A spokesperson for the New York City Metropolitan Transit Authority (MTA) said in a statement to ABC News that “rules require non-service animals to be kept inside containers and not disturbing other passengers” and also explained that what’s shown in the video is disturbing and “a clear violation of our rules.”

MTA officials notified the New York City Police Department (NYPD) of the video Tuesday and the police department has launched an investigation into the incident.

Transit rules, as listed on the MTA website, state that “no person may bring any animal on or into any conveyance or facility unless enclosed in a container and carried in a manner which would not annoy other passengers.” These rules do not apply to “working dogs for law enforcement agencies, to service animals, or to animals which are being trained as service animals.”

If NYPD officers come in contact with unauthorized dogs or other animals aboard the New York City Transit system, they are required to eject the passenger with the animal from the train.

Officers are also required to issue a Transit Action Bureau (TAB) Notice of Violation, for which the fine is $25. In 2016, 119 unauthorized animal TAB summonses were issued by the NYPD. The number dropped to 85 in 2017 and thus far in 2018, 19 have been issued.

The woman that was attacked was not seriously injured, but the police continue to search for the dog’s owner.

It is unclear what the penalty will be if he is identified, but MTA Chairman Joe Lhota said in a press conference that “bringing a pit bull on board any of our subway systems is a violation of the law and a person who does that should be prosecuted to the full extent of the law.”

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