The area affected, covering 1 mile by 1.5 miles, is near West Calder and runs adjacent to the A70.

The Scottish Fire and Rescue Service (SFRS) is urging nearby residents to keep their windows closed this evening as the smoke plume moves in an easterly direction towards Edinburgh.

A spokesperson said: "We were alerted at 1.23pm on Wednesday, 10 August to reports of a fire in the open at High Camilty, West Calder.

"Operations Control has now mobilised twelve appliances to the scene, where crews remain in attendance as they work to make the area safe."