An evacuation order that forced nearly 250 people from their homes in B.C.'s North Okanagan is being downgraded to an evacuation alert.

Emergency program co-ordinator Brent Watson said crews have contained a huge blaze on the site of the Tolko sawmill near Armstrong, about 15 kilometres north of Vernon.

In Pictures: B.C. sawmill fire

People living in five trailer parks around the sawmill were forced out on Sunday because of health concerns due to choking smoke from a huge pile of burning sawdust and stacked logs.

Watson said homeowners could start returning to property in the Palisades, Belva, Eagle Rock, Meadow Ridge or Twin Firs mobile home parks late Monday morning but must be able to show proof of residency.

He also said they should remain ready to leave again, if conditions deteriorate.

B.C. Forest Service crews helped local firefighters contain the blaze, which also damaged an adjoining cattle auction business, although all the animals were saved.