Helicopters and water bombers which were grounded due to strong winds continued their fight against the flames on Saturday morning, the NTV news channel reported.

The fire started on Thursday and quickly spread to residential areas by winds blowing at 50kph.

Turkish interior minister Ali Yerlikaya said that 900 residents in five affected districts were evacuated overnight in Izmir.

A witness told AFP that thick smoke had turned the sky grey, with the smell of smoke hanging over the city, the third most-populated in Turkey.

“Currently, two planes and eleven helicopters are continuing to intervene,” said agriculture and forestry minister Ibrahim Yumakli, saying that residents of the city should not be “worried”.

Around 1,600 hectares have been affected, the minister said.

Six other fires continue to rage in forest areas in other cities in Turkey, including northwestern Bolu and Aydin in the west.

Scientists say climate change makes extreme weather events including heatwaves more likely, longer lasting and more intense.