A British Columbia woman was arrested and could be facing assault charges after she allegedly pulled a knife on a mother and her three children following a violent confrontation on a city bus.

Police said a woman boarded a bus in Langley, B.C. on Tuesday morning and got into an argument with the driver when she refused to pay her fare.  

Other passengers, including a mother and her three young children, complained about the woman's profane language and asked her to stop swearing.

One witness said the suspect then threatened to kill the mother and her children.

Darlene Henley told CTV Vancouver she heard the suspect saying: "I don't give a bleep, bleep about your kids. I'm going to kill them and kill you and spit on their graves."

That was apparently enough to set the mother off, who was captured on camera repeatedly punching the suspect.

The fight ended with the bus driver ejecting both women from the bus, but the confrontation didn't stop there.

Police said the mother and her children started walking towards a nearby mall, but the suspect followed and kicked one daughter, pushed over another and pulled out a knife.

The RCMP were called to the scene and arrested the woman within 20 minutes of the alleged assault. Officials said the suspect is known to police.

"We don't know anything about her mental health," Cpl. Holly Marks said. "We did take her to local hospital to make sure she was medically OK to be in custody, and the doctor indicates that she was."

The suspect was held in custody overnight and the RCMP is recommending charges of assault and assault with a weapon.

With a report from CTV Vancouver