Residents in Newhall, who were evacuated after a "potentially volatile substance" was found, have been told they will not be returning to their homes tonight.
Up to 200 people were asked to leave their homes at around 9.30pm after police discovered the substance at a flat and arrested a 55-year-old man.
Rich Davis told ITV News that his grandparents had been forced to stay with friends as police and fire crews continue work at the scene.
A school has been opened to provide shelter to those who need it, Mr Davis added.
More top news
David Cameron has been urged to accept thousands of unaccompanied child refugees from Syria.
The actor and musician, who played character Matt Musgrove on the soaps between 1998 and 2004, has died.
The family of a teenage boy who died after a hit-and-run in Leicester are urging the public to help find the driver of the car.