White House lockdown triggered by bang now lifted - media reports

A White House lockdown triggered by a loud bang just moments before President Barack Obama and his family were due to take off by helicopter from the South Lawn has been lifted, media reports said on Saturday. The reports quoted a Secret Service spokesman as saying a food vendor cart had caught fire nearby. A tweet by WTOP local radio quoted the Secret Service as saying the fire on a nearby street corner was not considered a serious threat and that the security situation was now contained. White