Several coaches caught fire in a serious blaze at a garage.
The single-decker buses were ablaze at the Apollo Auto Centre at the Lichfield Road Industrial Estate in Tamworth, Staffordshire.
The smoke plume from the fire could be seen for miles and people were urged to avoid the area.
Six fire engines had been called to the scene but this was later scaled down to two. Crews were expected to stay on site overnight.
Firefighters from both West Midlands and Staffordshire fire services were called to the scene at 13:30 GMT.
Resident Sarah Gayton said she saw "black thick smoke in the sky" from St Editha's Square, Tamworth, about a mile away from the fire.
"I heard lots of sirens and wondered what was going on and it soon became clear when I saw the smoke.
"You could taste the smoke in the air," she said.
Staffordshire Fire and Rescue Service said investigations at the site would continue on Sunday morning.