Work on the London 2012 Olympic Games momentarily came to a standstill on Wednesday, as workmen came face to face with a Nazi bomb left over from the Blitz.
A small incendiary device, around 1kg, was found on the east London site for temporary basketball training courts in Leyton Marshes.
Scotland Yard bomb disposal experts were called to the site to get rid of the unexploded ordnance, a 2012 official said.
An Olympic Delivery Authority spokesman said: "A small Second World War incendiary device, weighing around a kilogramme, was safely removed this morning from the site of a temporary Games-time basketball training venue on Leyton Marsh.
"A routine scan of the site in early February detected metal underground and because of this an ordnance (military weapon) expert was appointed to oversee the start of works.
"Police were immediately contacted after the device was discovered and it was later removed by specialist officers.
"At no time were nearby people or property put at risk and work has now resumed on site."
A Metropolitan Police spokesman said: "Police were called to Leyton Marshes to reports of a suspected unexploded Second World War bomb being discovered at the site.
"The area was cordoned off and the site evacuated as a precaution, whilst EOD (explosive ordnance disposal) officers made the bomb safe."