SAN DIEGO -- A horse trailer suspected of smuggling immigrants crashed on Interstate 8 about 55 miles east of San Diego Saturday, and about 20 people were spotted fleeing into a mountainous area.
The California Highway Patrol said 18 people were arrested.
At least one person had a gashed head from the wreck, which was reported on westbound Interstate 8 in Campo, about 15 miles north of the U.S.-Mexico border, just before noon.
The trailer, which was being pulled by a Ford F-250 pickup truck, overturned and had its top ripped off, according to the California Highway Patrol.
Kurt Zingheim of Cal Fire said that after arriving to the scene and finding the trailer empty, his agency worked with California Highway Patrol and Border Patrol agents to find victims from the crash.
At least 16 people were injured, according to Cal Fire San Diego spokesperson Isaac Sanchez.
Zingheim explained that first responders found many of the crash victims not far from the overturned trailer. Cal Fire set up a triage unit to assess each of their injuries.
Zingheim said the situation was difficult, because paramedics were trying to treat people who "didn't want to be found." Border Patrol agents were seen leading crash victims away in handcuffs.
Six people were taken to area hospitals, including two who were taken away by helicopter. CHP officials said their injures are non-life threatening.
Sanchez said authorities were continuing to search the area for more people injured in the wreck.