About 100 homes had to be evacuated after a large fire broke out at a commercial garage in Derby.
Residents spent the night at a refuge centre set up as crews tackled the blaze in Twyford Street, Normanton.
Derbyshire Fire and Rescue Service said the evacuation was prompted by "the presence of commercial cylinders".
Nearby roads remain closed following the fire on Saturday evening. One crew has stayed at the site dampening down the fire.
Bob Curry, from Derbyshire Fire and Rescue Service, said two families remained at the refuge centre at St Augustine's Church, Upper Dale Road, and will be offered hotel accommodation this evening.
The rest of the residents forced to leave their homes have now returned, he said.
Station manager Adam Bleakman said a joint police and fire investigation into how the blaze started had begun.
He added the "structural integrity" of the buildings affected would be examined.
We are currently dealing with a significant 8 Pump fire involving workshops behind the shops on Normanton Road. Full evacuation of the public in progress - it’s going to be a long night. @DerbyshireFRS @DerbysPolice @EMASNHSTrust pic.twitter.com/m0yVhNnZur— Bob Curry (@bob_rcurry) November 10, 2018
Mohammed Faiz, who lives with his family near the garage, stayed at the church overnight and has not been allowed home yet.
"Police [officer] knocked on everyone's house... he said 'we are not safe, everybody come outside'," he said.
"My wife and my two kids, one is three years and one is one year [and] six months, they were really very upset."
A number of roads are closed in #Normanton, #Derby tonight as we assist @DerbyshireFRS with a large building fire. Please avoid the area and listen to safety advice from the emergency services. https://t.co/WVATUAIQPJ— Derbyshire Police (@DerbysPolice) November 10, 2018
Grove Street and Normanton Road have reopened but Twyford Street and Harriet Street remain closed while investigations continue.