More than 70 percent of fires that have swept Italy this summer are caused by human action, aided by climate change, a government minister said Thursday.

Firefighting planes were deployed again overnight to tackle forest fires in the southern region of Calabria and on the island of Sicily, where flames threatened a nature reserve in the north.

A huge fire has torn through a northern California town, hours after officials urged residents to flee the powerful blaze. 

Downtown Greenville, a small community in the north of the state, was engulfed by flames after strong winds whipped the natural disaster towards the community.

Greek firefighters battled Thursday to bring under control two major fires raging near Olympia and on the island of Evia as the country swelters in a record-breaking heatwave.

More than 170 firefighters, around 50 trucks, six helicopters and water-bombing aircraft were deployed near the ancient archeological site, the birthplace of the Olympic games, on the Peloponnese peninsula.

Turkish rescuers on Thursday began evacuating hundreds of villagers by sea after a deadly wildfire engulfed the outer edges of a thermal power plant storing thousands of tons of coal.

An AFP team saw firefighters and police fleeing the 35-year-old Kemerkoy plant in the Aegean province of Mugla as bright balls of orange flame tore through the surrounding hills.

Rescuers used helicopters and water cannon Wednesday to beat back fires encircling a Turkish power plant in the second week of deadly blazes testing the leadership of President Recept Tayyip Erdogan.

More than 170 wildfires have scorched swathes of Turkey's southern coast and killed eight people since breaking out east of the Mediterranean vacation hotspot Antalya last Wednesday and then spreading west.

Fire-fighting resources from EU nations are on their way to Greece, Italy, Albania and Northern Macedonia to help fight forest blazes, the EU crisis management commissioner said on Wednesday.

"We are working around the clock to send help as fires rage across Europe," commissioner Janez Lenarcic said in a statement.

Farmer Mevlut Tarim says the furious fire that burned his cow alive, killed eight people and scorched vast swathes of Turkey was like an explosion.

"The fire happened in an instant," the 67-year-old told AFP after managing to pull and push some of his screaming animals through pitch-black smoke and patches of burning turf encircling his farm. 

At least 16 people have been killed and a quarter of a million people displaced from their homes after heavy monsoon rains lashed eastern India, officials said Tuesday, as the air force joined rescue efforts.

The latest deaths in West Bengal came a few days after 11 people were also killed in the state as the torrent of water swept away homes and triggered landslides.

Climate scientists have long warned that the 21st century would see more natural disasters made worse or more likely by global warming.

But a cascade of deadly extreme weather this summer in the northern hemisphere could make 2021 the year when climate predictions became a reality that can no longer be ignored.

China's climate envoy on Tuesday said the world's most populous nation would release its updated plans to reduce carbon emissions "in the near future" as nations prepare to meet later this year for a pivotal global conference.

Climate negotiators from 196 countries and the European Union as well as businesses, experts and world leaders will gather in Glasgow in November for the COP26 summit.