Authorities in Athens have announced the closure of the Acropolis for a number of hours due to heatwave temperatures.

The ancient site in the Greek capital – which drew nearly four million visitors last year – was closed from midday until 5pm on Wednesday as the temperature was set to reach 39C.

Some school classes were also cancelled in parts of southern and central Greece where the temperatures were highest.

Conditions worsened in an area north of the capital, after a fire at a cookware and food container factory sent clouds of thick black smoke into the sky.

Mobile phone alerts sent by a government disaster response agency urged residents in the area to remain indoors.

In Athens, city authorities announced that rubbish collections would also be halted for several hours and that seven air-conditioned spaces would be opened to the public.

Drones with thermal cameras were being used in Athens to co-ordinate the public health response, officials said.

Cooler weather is expected on Friday.