Portugal remains on high alert today as forest fires continue to rage across the country. Eight blazes are reportedly out of control - the worst in Valongo near the northern city of Porto. Soaring temperatures and tinder dry conditions are partly to blame.

However authorities say between 20 and 30 percent of the fires have been deliberately lit. Portuguese police have already captured 18 suspected arsonists, with more arrests expected in the coming days.

Across the border in northern Spain, emergency workers are still trying to contain fires in the northwestern region of Galicia, which have left three people dead and devastated some 5,000 hectares of land.

Evidence is mounting that most of the fires have been deliberately set, prompting authorities to make several arrests. Volunteers and aircraft are providing backup to firefighters.

But with high temperatures set to continue, they face a daunting challenge to bring the flames under control.

PHOTO CAPTION

A bulldozer moves dirt to try to extinguish a wildfire Tuesday, Aug. 8 2006, near Valongo, east of Porto, northern Portugal. Some 300 firefighters have been fighting the fire that started Monday. (AP)