VILA DE REI/MACAO, Portugal (Reuters) – Fires that swept across central Portugal for nearly 48 hours were under partial control on Monday, but adverse weather conditions are raising concern they will flare up again.

The last of three wildfires that broke out on Saturday in Castelo Branco, a district 225 km (140 miles) northeast of Lisbon, is now 90% under control, a Civil Protection official said early on Monday.

Trees are seen after a forest fire near the village of Cardigos, Portugal July 22, 2019. REUTERS/Rafael Marchante

Reminding that firefighters have a “very difficult day” ahead, the official said the wildfire is still 10% active and the remaining flames require “a lot of attention”.

Around 1,040 firefighters are on the ground, backed up by 332 firefighting vehicles and five airplanes, according to Civil Protection.

After spreading to the neighboring Santarem district, the three wildfires threatened several villages in the Vila de Rei and Macao municipalities, forcing evacuations and injuring 31 people, one in serious condition.

A number of municipalities in Santarem and Castelo Branco are still considered at maximum risk of fire, according to the national meteorological agency. Temperatures could reach 40 degrees Celsius (104 degrees Fahrenheit) in some areas on Monday. Low humidity and moderate wind is also expected.

(Reporting by Catarina Demony in Lisbon and Miguel Pereira and Rafael Marchante in Vila de Rei and Macao; editing by Axel Bugge, Larry King)