Sydney, Oct 9 (IANS): Bushfires raging in eastern Australia's city of Casino have destroyed at least 20 houses and burnt some 100,000 hectares of land, authorities said on Wednesday.

More than 40 fires are active in the state of New South Wales while dangerous conditions continue, especially amid the blazes of Drake and Busbys Flat, near Casino, despite temperatures going down.

The Drake and Busbys Flat fires have claimed 90,000 hectares of land, the Efe news reported.

The Rural Fire Service on Tuesday issued an alert over four different blazes raging some 100 kms apart, with two of them joined overnight causing major damage.

Rappville, with some 250 residents to the south of Casino, is the most affected by the fires along with Edwinger, southwest of the city in the interior of New South Wales.

Australian Prime Minister Scott Morrison on Wednesday told media that some 20 houses were destroyed in the fires and showed his support to those affected.

In the neighbouring state of Queensland, firefighters are trying to control about 30 fires in the south where at least one house was destroyed.

The fire season in Australia varies according to the area and weather conditions, but it generally coincides with the extended summer period (December to March).

The worst fires in Australia were recorded in February 2009 in the south eastern state of Victoria, when 173 people died and 414 were injured in blazes which destroyed an area of 4,500 square kms.