String of fires in WA 'deliberately lit'

Police are hunting an arsonist after a string of deliberately lit fires broke out northeast of Perth less than 24 hours after another suspicious blaze wrecked five classic cars.

Arson squad detectives are investigating at least seven deliberately lit fires that started along O'Brien Rd and Lancewood Rd, Gidgegannup about 5.30am.

Thirteen crews brought the fires under control on Thursday morning.

Those blazes came after a deliberately lit bushfire threatened lives and homes at Boya in the Perth Hills on Wednesday afternoon.

The 2ha fire was brought under control but not before it destroyed seven cars - five of them part of a classic car collection - and licked at the edge of a house all belonging to a Boya resident.