NBC producer Kristen Welker has reported that the US Secret Service has revoked the top secret security clearances of all 11 agents and officers.
"Pending investigation, their top secret clearance has been revoked," George Ogilvie, a Secret Service spokesman, said.
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After the heatwave come the storms, with lightning flashes illuminating the night sky across much of the country last night.
An Independence Day event at a UK base has been cancelled by the US Air Force over security fears.
British firms predict the economy should sustain a "solid" pace of growth for the rest of the year thanks to lower oil prices and inflation.