Authorities say there were reports of shots fired at about 11 a.m. in the area of Williams Canyon and Santiago Canyon roads.
According to deputies, a mother managed to help three people -- believed to be children -- leave the center. But seven to eight other people, which included horseback riders who were there for lessons, were told to stay in place at the Jackson Ranch Equestrian Center.
A SWAT team arrived to search the center and remove the people inside.
"Every couple minutes, you hear gunshots. I didn't think much of it, but eventually it got worse when I left. They started hitting trees and my trainer felt them brush beside her," said 16-year-old witness Viviana Vidaurre, who was at the center for riding lessons. "I was in shock that people were almost hitting us and the horses and the students."
Shortly after the shots were fired, a white compact car was seen leaving a property along Santiago Canyon Road and got into a single-vehicle collision. The male driver was detained. His name was not immediately released, but investigators are calling him a person of interest.
A woman who was in the home where authorities believe the shots were coming from was also detained as a person of interest. It's unclear if the man and the woman know each other.
There were no reports of injuries.