F-16s intercept plane near Obama's helicopter at LA airport

U.S. President Barack Obama walks on the South Lawn of the White House, February 15, 2012.

LOS ANGELES (Reuters) - U.S. F-16 fighters intercepted a small plane that strayed into restricted airspace around President Barack Obama's helicopter on Thursday in Los Angeles, and more than 20 pounds of marijuana was later found aboard the intruding aircraft, officials said.

The two F-16s were scrambled from March Air Reserve Base, east of Los Angeles, by North American Aerospace Defense (NORAD) Command officials alerted to an airspace violation "in the vicinity" of Los Angeles International Airport, a NORAD spokesman said.

The fighter jets made contact with the pilot of the Cessna 182, a single-engine plane, and "he was compliant once the intercept was made and he was instructed to land at Long Beach Airport, which he did without incident," the spokesman, Michael Kucharek, told Reuters.

U.S. Secret Service spokesman Ed Donovan said agents questioned the pilot and determined that there was no apparent intention to harm the president.

There was no immediate word on whether criminal charges were filed in connection with the incident. But a law enforcement source who has been briefed on the incident said authorities found 10 kilos, or 22 pounds, of marijuana on the plane.

Obama flew on the White House helicopter, Marine One, from Los Angeles to the seaside community of Corona Del Mar and back on Thursday morning for a fundraiser.

Members of the White Houses press corps made the same journey in another Marine helicopter that flew nearby. There was no sign of disruption or incident from the air.

After arriving back in Los Angeles, the president boarded Air Force One and flew to San Francisco.

(Additional reporting by Alister Bull and Dan Whitcomb; Editing by Cynthia Johnston and Todd Eastham)