The forest fire north of Zaragoza started on Wednesday and has spread overnight into Friday, local authorities say. In terms of area, it is now the largest in Spain this year.
"The night has been very complex and very difficult," said Roberto Bermúdez de Castro, head of security in the regional government in Aragon, according to Spanish media.
Hundreds of firefighters and military personnel, as well as more than 30 firefighting aircraft, are now battling the flames. The risk of the fire spreading is assessed as imminent.
Last week, 13 people died in another forest fire in Spain, in Almería in the southern region of Andalusia.
