NEW: The bomb has been safely defused and removed, says London Fire Brigade
The 550-pound device was uncovered by construction workers at a site in Bethnal Green
It's thought to have been dropped during German bombing raids in the early 1940s
Military bomb disposal experts safely removed an unexploded World War II bomb from a basement in East London on Tuesday, after its discovery forced scores of people from their homes overnight.
The 250-kilogram (550-pound) device had lain undisturbed for more than 70 years but was uncovered Monday afternoon by contractors working at a construction site on Temple Street in bustling Bethnal Green.
Almost exactly 24 hours later, it had been made safe and removed, London Fire Brigade said, adding that residents who were evacuated from their homes would soon be allowed to return.
The device is believed to have been dropped over London during German bombing raids in the early 1940s but didn’t detonate, the UK Ministry of Defence said.
A military bomb disposal team worked through the night to defuse the device. Images provided by the ministry showed the rusty device firmly embedded in the dirt, in the cellar of a three-storey building.
A military spokesman said before its removal that the bomb, if detonated, “could cause mass destruction” and that it was potentially more dangerous today than when it was made.
At least 150 people were evacuated from their homes overnight Monday to Tuesday, a 200-meter exclusion zone was set up and several roads were closed.
A local school was called into action as an emergency shelter for those unable to go home, Tower Hamlets Council said.
Military bomb disposal experts from the Royal Logistics Corps detonated similar devices discovered in London’s Wembley and Bermondsey areas earlier this year.
London Fire Brigade said it had been called out for nine unexploded WWII bombs since 2009.
German planes dropped thousands of bombs on London during the Blitz, from September 1940 to May 1941. Rocket attacks on the capital followed later in the war.
According to the Imperial War Museum, it’s estimated more than 12,000 metric tons of bombs were dropped on London and nearly 30,000 civilians were killed by enemy action.
A searchable map produced by the Bomb Sight Project shows the scale of the Blitz bombing.
CNN’s Elaine Ly contributed to this report.