Over 100 wildfires in northern Portugal have overwhelmed firefighters, resulting in seven deaths since the outbreak began over the weekend.

Prime Minister Luís Montenegro declared a state of calamity for affected areas, mobilizing additional resources and calling for investigations into the fires’ origins.

As of Tuesday, more than 15,000 hectares (37,000 acres) were scorched, threatening a region home to 210,000 people.

Extreme weather has coincided with flooding in central Europe, highlighting climate issues.

Spain and other EU countries have sent firefighting assistance, while smoke has impacted visibility across the border into Spain.

Authorities have arrested seven individuals suspected of arson and prohibited heavy farming equipment to mitigate fire risks, NPR has reported.

The situation is complicated by the difficult conditions for air support due to thick smoke.

Written by B.C. Begley