Homes in Croxley Green had to be evacuated after a 20ft deep sinkhole emerged in the back garden of one of the properties.
Police were called to the house in Dugdales at around 6pm yesterday after the hole, which is approximately 5ft by 5ft wide, was discovered.
As the sinkhole was close to the property, a house and three flats, in the cul de sac were evacuated.
Residents were not allowed back into their homes this morning.
Comment: Sinkhole appears in Hemel Hempstead, UK - Fourth major sinkhole to hit country in two weeks
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