WH: Secret Service did their job

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The White House on Thursday said the Secret Service “took the precautions necessary” to ensure President Obama’s safety during this week’s memorial service for Nelson Mandela in Johannesburg.

The security situation at the memorial was called into question Thursday after a sign-language interpreter who stood on stage with President Obama said he is schizophrenic and was hallucinating during the ceremony.

White House press secretary Jay Carney said he could not discuss the steps taken by the Secret Service ahead of the president's visit and refused to say whether there are standard protocols to vet individuals with whom the president appears.

But Carney said he could assure the public "that when the president travels, notably when he travels abroad and especially in a circumstance like that … the Secret Service works very hard to take the necessary precautions."

Read more from The Hill.