A suspected unexploded World War Two bomb found in the River Thames has been recovered for safe disposal.
The operation by the Royal Navy and Metropolitan Police forced Waterloo Bridge, Westminster Bridge and Victoria Embankment in central London to shut.
Westminster Police said the device was “being towed for safe disposal/removal elsewhere” as they reopened the riverfront at about 03:00 GMT.
Police were called to the river at 17:15 GMT on Thursday.
The Port of London Authority said the suspected bomb measured “2ft by 1ft” (60cm x 30cm).
The device has been referred to as an “ordnance” which in armed forces terms can refer to either explosive weapons or ammunition.
Kris Van de Sander, a freelance journalist from Belgium, told the BBC “massive crowds” had spread around Westminster Bridge.
He said: “Everyone was a little paranoid.”
Westminster Tube station was shut but has since reopened, as have the bridges, all surrounding roads and a section of the river between Westminster Bridge and Hungerford Bridge which had been closed overnight.
In November, a shopping centre and homes were evacuated and ferry services halted when a World War Two bomb was found in Portsmouth Harbour.
The device was towed out to sea and blown up.
An unexploded World War Two bomb was also uncovered by builders near Wembley Stadium in north-west London in 2015.
The Army said it posed “a genuine risk to life” but it was removed by a specialist team and safely detonated.