(AFP) - The death toll from floods that have devastated northeastern Italy rose to 13 on Thursday, according to media reports, driving thousands from their homes and destroying crops in an area known as the country's orchard.

Rescue workers have been searching for anyone trapped by floodwaters in the Emilia Romagna region.

Authorities have not confirmed the latest rise from the 11 deaths previously announced.

Among the victims were two farmers in their 70s who may have been electrocuted while trying to move a fridge inside a flooded house, Italian media reported.

With 10,000 people already displaced, authorities in Ravenna issued an immediate evacuation order early Thursday morning for three more villages threatened by floods.

"There is a hole in the dyke, so if it were to start raining again... we fear that the water could rise again, this is our biggest fear," Andrea Ancherani, a resident of Bagnara di Romagna near Imola, told AFP.

Locals waded through dirty water or reclaimed what they could from sodden houses in towns across the wealthy region, famed for its historic cities and prized gastronomy.

Authorities said electricity had been partly restored, but some 27,000 people were still in the dark.

Nearly two dozen rivers and streams flooded across the southeast of the low-lying region following heavy rain earlier this week, submerging entire neighbourhoods and farmland, and damaging 400 roads.

Agricultural lobby Coldiretti said Thursday that more than 5,000 farms were under water, with drowned animals and tens of thousands of hectares of vineyards, fruit trees, vegetables and grain flooded.

As the water receded in some areas, residents were left cleaning homes and streets thick with mud and filled with debris.

In Lugo, near Ravenna, Flavio Abbondanti, 39, was waiting for the water that had inundated his home to subside so he could get to work.

"We used what we could find from a work site to make a little barrier, but (the water) still came in," he said.

- Wall of water -

The mayor of Ravenna, Michele De Pascale, announced Thursday that residents of about a half dozen towns could return, but warned them "to exercise the utmost caution".

Cracks in river embankments still posed a risk to other areas, which were being closely monitored, he said.

The dead included a couple in Ronta di Cesena believed to have been hit by a wall of water as they went to check on their herb farm.

The body of the woman, in her 60s, was pulled 20 kilometres (12.5 miles) by rushing waters to the beach in Cesenatico, according to SkyTG24.

There was little significant rainfall on Thursday and only light rain expected Friday, though authorities said the high level alert for rivers remained.

Two people died in the same region earlier this month after two days of almost continuous rain.

"We had an estimated two billion (euros) of damages two weeks ago... the ground no longer absorbs anything," Stefano Bonaccini, president of the Emilia Romagna region, told La7 television channel late Wednesday.

"When we have six months of rain in 36 hours, falling where there had already been record rain two weeks ago, there is no territory that can hold out."

Experts warn such disasters are becoming the norm due to human-induced climate change which is exacerbating both droughts and storms.

- 'Shocking disaster' -

On Thursday Bonaccini compared the floods to the earthquake that hit the region on May 20, 2012, almost 11 years ago to the day.

Fixing the damage would be "a gigantic undertaking", he said, and the region launched a fundraising effort.

Ferrari, the luxury carmaker whose Maranello base is not far from the flooded areas, pledged one million euros ($1.1 million).

The flooding caused the cancellation of Sunday's Formula One Emilia Romagna Grand Prix in Imola.

Italy's armed forces and the coastguard joined the rescue effort, deploying helicopters to lift desperate residents from their homes and inflatable boats to reach houses surrounded by water.

Pope Francis offered his prayers for those affected and thanked everyone on the ground helping those hit by the "shocking disaster".

Agriculture Minister Francesco Lollobrigida said Wednesday that the government could not yet quantify the overall damage to the region while vast areas were still flooded.

© Agence France-Presse