Businesses and buildings were evacuated after a chemical and gas leak from a lorry in Oldham.
Five fire engines and an incident command unit were sent to West End Street at about 15:15 BST, said Greater Manchester Fire & Rescue Service (GMFRS).
“Firefighters wearing PPE and using specialist equipment worked alongside partners to make the vehicle and surrounding area safe with some nearby businesses and buildings evacuated while this took place,” said a GMFRS spokesperson.
People were advised to avoid the area and residents were urged to keep their windows and doors closed.
Fire engines from Ashton, Heywood, Mossley, Rochdale and Bury went to the scene, along with the incident command unit from Rochdale fire station.
The GMFRS spokesperson later added: “The incident has now been scaled down with no wider threat to the public while crews work with partners to decontaminate the affected area so businesses can return to the site.”
The fire service said it was likely to remain at the scene overnight.