Trees were uprooted, vehicles damaged and power supplies disrupted by winds gusting up to over 60 km/h in the central province of Henan.

Hail facts

The largest can weigh a little under 1 kg and fall at more than 50 metres per second Hail storms can devastate entire fields of crops in a few minutes The biggest hailstones in the world tend to fall in north-east India In Britain there were last hailstorms with tennis ball-size hail stones in Wokingham in 1959

Most of the deaths came when buildings in the northern town of Zhengzhou collapsed including a petrol station.

In the neighbouring village of Yilin, a cattle feed factory collapsed killing four, the Beijing Youth Daily reported.

Hospitals were overcrowded with victims suffering from injuries caused by the hailstones and by flying debris.

The Henan Province Meteorological Station said it had issued a severe weather warning, but it had failed to reach the public in time.

Livestock killed

"We said there would be a thunderstorm. It's difficult to predict hail," said station manager Gu Wanlong.

Zhengzhou Mayor Yao Daixian told Xinhua news agency he had demanded stricter housing standards.

According to BBC weather experts, most hailstones are smaller than 2.5 cm (1 in) in diameter.

Floods have affected more than 100 million people in China

However, they can be as big as grapefruits.

Last year, livestock, houses and farmland in seven villages were destroyed by hailstones the size of footballs and weighing up to two kilograms in the northern Nigerian city of Kano.

China is still battling with the worst flooding for a decade.

Officials said that more than 800 people have died and 100 millionaffected by the floods, which have destroyed more than eight million hectares of crops.

Southern and western provinces suffered the biggest losses and more than 1.5m people have had to leave their homes