Los Alamos nuclear secrets missing

The United States government has begun an urgent investigation into the disappearance of classified information from the nuclear weapons laboratory at Los Alamos in New Mexico.

The laboratory director, John Browne, said officials were treating the missing secrets as an extremely serious matter and were taking swift action to deal with it.

According to a report in the New York Times, the material was contained on computer hard drives locked in a vault in the area where nuclear weapons are designed.

The Energy Department said there was no evidence of espionage at this stage, prompting speculation the information may have been mislaid during forest fires which forced the evacuation of the facility last month. A BBC correspondent in Washington says it's another embarrassing security breach for the government, following the arrest last year of a Los Alamos scientist accused of stealing nuclear secrets.

From the newsroom of the BBC World Service