The area of devastation has been calculated from information received from firefighters as well as from drones and satellite images.
Four planes have been used to help contain the fire and the Polish State Forests are planning to add a helicopter as heavy fire engines find it hard to reach some parts of the park, especially the swamp areas.
The firefighters are being supported by territorial defence forces, park workers, local governments and local residents.
Biebrza National Park covers a total area of 59,000 hectares and protects valuable swamplands which are home to a range of rare bird species as well as moose.
Fires in the national park happen every year, but usually do not exceed a total area of 200 hectares over a 12 month period. The park has not seen a disaster of comparable scale for more than 12 years. Nearly all the fires are the result of human actions, intentional or accidental.
On Wednesday, PM Mateusz Morawiecki decided to channel an additional PLN 600,000 (EUR 132,000) to fight the fires, government spokesman Piotr Mueller announced.
The operation has already cost PLN 500,000 (EUR 110,000), according to the Polish State Forests. (PAP)
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