PINE VALLEY (KGTV) - Nineteen people are in custody after the horse trailer they were traveling in crashed Saturday on Interstate 8, about 55 miles east of San Diego, Border Patrol said.

The trailer, which was being pulled by a Ford F250 pickup truck, separated from the truck and overturned on its right side just before noon, according to the California Highway Patrol.

Border Patrol agents said that the trailer was smuggling people into the country and all of the apprehended people identified as Mexican nationals. The driver of the truck managed to escape, according to Border Patrol.

Six people were injured in the crash and two of them had to be airlifted to a hospital for treatment, Border Patrol told 10News.

Witnesses said people ran out of the overturned horse trailer. Border Patrol agents took 19 people into custody and continued to look for others that may have fled on foot.