A huge rocket carrying a spy satellite for the United States has launched from the central California coast.

United Launch Alliance says liftoff occurred Wednesday morning from Vandenberg Air Force Base, about 150 miles northwest of Los Angeles.

The 23-story Delta IV Heavy _ the largest rocket in the country _ carried a satellite for the National Reconnaissance Office, which operates the nation's system of intelligence-gathering satellites.

Since the mission is classified, no other details were available.

It's the second time this type of rocket has launched from the West Coast base. The first occurred in 2011 and shook the nearby city of Lompoc. Some spectators reported hearing the rocket's roar from 50 miles away.

For the latest launch, base officials closed a nearby beach as a precaution.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

A powerful rocket carrying a National Reconnaissance Office satellite is expected to be launched into orbit Wednesday from the California coast.

The 235-foot Delta IV Heavy rocket is scheduled to lift off from Vandenberg Air Force Base at 10:52 a.m., according to United Launch Alliance.

The rocket is set to send a classified spacecraft into orbit for the NRO, which is in charge of U.S. intelligence-gathering satellites.

Air Force security and police have closed nearby locations as a precaution.

It's the second time that a Delta IV Heavy rocket will be launched from Vandenberg. In January 2011, a sound wave as loud as a freight train swept over nearby Lompoc, a town of about 43,000. Some people reported hearing the rocket's roar as far away as 50 miles.

United Launch Alliance is a joint venture of Lockheed Martin Corp. and The Boeing Co. to provide space launch services to the U.S. government with their Atlas and Delta rocket programs.