Police have arrested two people and installed a 100-metre cordon around a property in Chelmsford, Essex, after a search involving explosives.
Essex Police said a 34-year-old man from Chelmsford was in custody on suspicion of an offence under the Explosive Substances Act 1883.
A 33-year-old woman from Ongar was also arrested.
As part of an ongoing investigation, police searched the property in Meadgate Avenue and found items which they said “require specialist focus”.
A police statement said: “A number of properties in the area have been evacuated, with a 100-metre cordon put in place as a precaution.
“This is to ensure the safety of the community and to allow specialists the time and space to work.”
According to Essex Live, one eyewitness reported seeing police cars, forensics, the bomb squad and military at the block of flats, while nearby houses were evacuated.
It reported that makeshift rest stations have been set up at a nearby church and school for people evacuated from within the cordon.