Law enforcement said someone made a bomb threat at 7:45 a.m., nearly three hours before the theme park at 26101 Magic Mountain Parkway was scheduled to open. The threat triggered a massive response from firefighters, the Los Angeles County Sheriff's Department and California Highway Patrol.
Aerial video from AIR7 showed a fire engine and more than a dozen LASD vehicles at the scene, including an armored vehicle that was part of the sweep by deputies.
Sheriff's deputies and CHP officers completed the sweep of the sprawling theme park and said they found nothing suspicious. The "all clear" was given around 11 a.m.
The park was closed at the time of the threat and did not reopen until 12:30 p.m. due to the law enforcement activity.
"The park appreciates the timely response by both law enforcement agencies and values the ongoing partnership and commitment to keeping our community and guests safe," a Magic Mountain spokesperson said in a statement provided to ABC7.
Details of how the threat was communicated were not available.