A woman who was attacked along with her husband by a gang of bikers on the West Side Highway said on Tuesday that the motorcyclists were using knife handles to hammer on a window of their car just before her husband raced away, running over one of the men and breaking his spine.

In an emotional testimony, the woman, Rosalyn Ng, described the attack at the trial of two men — one an undercover police officer — who are charged with gang assault in connection with the attack.

Ms. Ng made it clear that she and her husband, Alexian Lien, feared for their lives on Sept. 29, 2013, when they were surrounded by dozens of bikers on a scofflaw tour of New York who forced them to stop on the highway, just north of 125th Street. Their 2-year-old daughter was in a car seat in the back of the Range Rover.

The bikers were yelling things like “I am going to kill you,” she said during testimony in State Supreme Court in Manhattan. One hammered on her passenger window with a large black serrated knife, and she saw others with knives, hitting and rocking the vehicle, she said.