Firefighters have been tackling a fire at a scrap metal recycling yard in north Liverpool.
The alarm was raised just after 4am. Crews arrived at the scene at Alexandra Dock, Bootle, minutes later.
Twelve fire engines have been at the scene at European Metal Recycling where it is believed plant machinery and storage areas have been affected.
A large plume of smoke can be seen in the local area.
Public Health England is advising local residents to stay indoors, keep windows and doors closed.
Motorists travelling through the area are advised to keep windows closed, turn off air conditioning and keep air vents closed.
Merseyside Fire and Rescue says the fire poses a low health risk to people in the local area.
The Environment Agency is monitoring the situation.