Central London security alert shuts The Mall
Several roads in central London have been closed after two security alerts.
A disturbed manhole cover sparked an alert which resulted in the closure of The Mall and Carlton House Terrace, a Metropolitan Police spokesman said.
The force said the the incident was "routine" and "ongoing" and the roads remained closed.
Roads around Northumberland Avenue were also closed while a bag was destroyed in a controlled explosion. The roads have now reopened.
Police said the bag was no longer deemed suspicious.
Eight vehicles from the ambulance service, including a command and control unit, were parked on the Mall although only two were ambulances.
Police were manning cordons and police with dogs were also present.
A police spokesman would not confirm whether the police response was connected to the forthcoming state visit by US President Barack Obama.
Mr Obama is due to visit London from 24 to 26 May.