The White House was put on lockdown for over an hour last night after a smoke bomb was thrown over the compound's fence, security officials said.
No one was injured and no arrests were made, the Wall Street Journal reported. The object was removed and the all-clear was given later Tuesday evening.
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The smoke bomb was thrown amid Occupy DC protests outside the White House, Secret Service spokesman George Ogilvie told Reuters. There were between 1,000 and 1,500 people present at the time.
According to the Washington Post, a plume of smoke rose into the sky – which protesters initially mistook for tear gas.
Police forced protesters back to allow them to search the area, the Daily Telegraph reported. There were not said to have been any confrontations.
President Barack Obama and his wife Michelle were not in the White House when the smoke bomb was thrown, but returned from a restaurant to find the compound shut down and an investigation underway.
According to Reuters, reporters from the White House press pool were prevented from leaving for about 45 minutes before they were escorted off the grounds. Part of Pennsylvania Avenue, the street that runs between the White House and the Capitol, was also closed during the investigation.
Earlier Tuesday, police made four arrests after hundreds of Occupy protesters gathered on Capitol Hill as lawmakers returned from the winter break, the BBC reported.
Protesters say they are fed up with the influence they claim money has over politicians and politics.
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