Up to 60 firefighters are tackling a blaze in the roof of a hotel on the outskirts of Bristol.
Avon Fire and Rescue were called to the Premier Inn, on Catbrain Hill, just after 13:15 BST, amid reports of smoke and explosions in the roof.
Operations would continue “for some time” after the fire spread quickly causing structural damage, it said.
The smoke can be seen from the nearby M5 and the Cribbs Causeway shopping centre.
A fire brigade spokesman said it was asking residents and businesses nearby to close doors and windows where possible.
“Operations will continue for some time as we get the fire under control,” a fire brigade statement said.
“Staff have worked hard with our partner agencies to ensure the local community remains safe and the cordons will remain in place for public safety.”
Avon and Somerset Police warned of “significant delays” in the Cribbs Causeway area adding the force had declared a major incident.
“This is due to the level of resources required by emergency services at a time when they are already stretched following protest activities in Bristol city centre this week,” a force spokesman said.
The A4018 Cribbs Causeway, which runs past the hotel, is closed in both directions between Clifton Rugby Club and Lysander Road.