LISBON, Portugal (AP) -- Strong winds and sweltering temperatures fueled some 20 wildfires across drought-stricken Portugal on Thursday as the number of firefighters on duty nearly doubled compared to the previous day, authorities said.
The day began with 10 major blazes and the number doubled by mid-afternoon as temperatures soared above 40 C (104 F) . Nearly 1,600 firefighters tackled the blazes, patrolled high-risk areas or cleaned up scorched areas, the Civil Protection Service said.
They were supported by 457 vehicles and nearly two dozen planes and helicopters dropping water. On Wednesday, about 900 firefighters were on duty.
Flames engulfed about a dozen rural houses, including several holiday homes, officials said.
Most fires were in heavily wooded areas of northern Portugal. A smoky haze from the fires covered Porto, the country's second-largest city, television images showed.
Temperatures in some regions were forecast to reach 45 C (113 F), the weather service said.
The Fire Prevention Agency placed most of Portugal on maximum alert as the country endures its worst drought on record. The heat wave is expected to continue through Saturday.
Fires have charred more than 68,000 hectares (168,000 acres) of parched woodland this year, more than half of it last month, according to the General-Directorate for Forests.
