Weather experts are warning that a dangerous heatwave is putting lives at risk in parts of Europe.

Meteoalarm - a pan-European operation made up of dozens of national weather services - has warned that "major damage and accidents are likely, in many cases with threat to life".

It has issued red alerts - considered "very dangerous" and meaning "exceptionally intense meteorological phenomena are forecast" - for parts of Italy, Switzerland, Croatia and Poland.

Orange alerts - which mean dangerous weather is expected - are in place in Spain, southern France, Greece and much of the Mediterranean.

"Lucifer" heatwave

Temperatures have exceeded 40C in places and the hot weather looks likely to continue into next week.

Dozens of forest fires are burning throughout the Balkans, with Albania asking the European Union for help.

Farmers are also warning that the intense heat will have a significant impact on crops.

Several deaths have occurred as a result of the heat, including a woman in the Italian Alps whose car was washed down a mountain after the heatwave triggered storms.

The heat has also caused at least one death in Romania and another in Poland, and dozens more people have been taken to hospital with sunstroke.

Keepers at Budapest Zoo in Hungary have been using huge ice blocks to cool down two polar bears.

Italian authorities have put severe weather warnings in place for 26 cities, including the tourist hubs of Venice and Rome.

At-risk population

Aid agencies are providing water and shelter to those in need.

Jeya Kulasingam, from the Red Cross, said: "This prolonged period of extremely hot weather is particularly dangerous for people with existing health problems such heart conditions, high blood pressure and asthma, as well as older people and children."

Carlo Petrini, founder of the Slow Food movement, wrote to Italian newspaper La Stampa warning that Italy's grape harvest risked being "cooked by the sun and the burning heat".

Experts say the worst could be yet to come.