According to authorities, 30 police horses have stampeded down one of Mexico City's busiest avenues, Circuito Bicentenario, injuring one person and damaging 11 cars.
The police have issued a statement that the city's government will pay for the damage to the vechicles and reassured the city that the injured person had only minor injures.
The horses were used to control protesters, however beame frightened by the sound of car engines as they were bring taken out of their trailers near Congress, police say.
Some horses were injured and have been treated by a veterinarian.
A motorist recorded the footage of the stampede and posted the video on YouTube.