30 police horses stampede through Mexico City (VIDEO)

Residents of Mexico City got a scare on Monday when 30 police horses escaped their handlers and stampeded down one of the capital's busiest avenues, damaging 11 cars and injuring one person.

Police said the horses were startled by the sound of car engines as they were being taken from their trailers near the Congress building, the Associated Press said.

They were getting ready to join their fellow officers in helping to control protesters when they broke loose.

"I had stopped at the traffic light when I heard the horses coming," one eyewitness said. "A horse hit the car.

"The horse fell, got up and continued."

While the person who was wounded only suffered minor injuries, police said several others were "severely frightened" by the incident, the Mirror reported.

Many of the horses also had to be treated by a veterinarian for cuts on their muzzles and legs.

Mexico City's government has promised it will pay for the vehicles damaged by the runaway horses.

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