Authorities urged residents in parts of Thessaloniki, Greece's second largest city, to remain indoors and shut their windows and doors due to toxic smoke from a burning recycling plant that was engulfed by a wildfire.
Another major wildfire broke out on Sunday afternoon west of the Greek capital, Athens.
The fire department said 210 firefighters, backed up by volunteers, specialised teams and 29 aircraft, including water-dropping planes and helicopters, were deployed to battle the blaze burning through pine forest in the Mandra area.
Authorities were racing to contain the blaze before nightfall, when aircraft can no longer perform firefighting operations.
In central Portugal's Vouzela area, more than 1200 firefighters backed up by nearly 400 vehicles and 15 aircraft tried to put out a blaze that broke out on Thursday, according to the Civil Protection authority.
The wildfire had burned across an area of 12,000 hectares by Sunday, information from the European Union's Copernicus satellite mapping agency showed.
The EU Civil Protection and Humanitarian Aid said that Spain sent 120 firefighters and 45 vehicles as reinforcements to Portugal on Friday, while three firefighting aircraft from Italy and Spain were also dispatched to help.
By Sunday afternoon, the fire appeared to be abating somewhat, with Portuguese media quoting officials as saying it no longer had major active fronts but that some hot spots remained.
In Spain, a wildfire burning since Friday in the northeastern Girona region had burned nearly 2200 hectares, the EFE news agency said. Catalan Fire Service head of operations Eduard Martinez said the blaze had a perimeter of 40km and firefighters may not be able to bring it under control on Sunday.
On the other side of southern Europe, in Greece, a fast-moving blaze at a recycling plant broke out Saturday evening near the Oraiokastro suburb of Thessaloniki, triggering evacuation alerts for three suburbs and a facility housing 157 people with disabilities.
Strong winds fanned the flames, and around 160 firefighters were deployed to battle the flames through the night until water-dropping aircraft could take off at dawn, the fire department said.
A 76-year-old man was arrested on suspicion of having started the blaze through negligence by generating sparks with his vehicle that set vegetation near the road alight, the fire department said.
The fire came days after another wildfire in a nearby area killed a 12-year-old boy and his father.
Fire department spokesman Brigadier Ioannis Artopoios, speaking on ERT TV on Sunday, said that about 85 per cent of wildfires in Greece were caused by negligence, including through sparks generated through the use of agriculture machinery, discarded cigarettes and the use of outdoor barbecues.
"This means most of them could have been avoided," he said.
