At least eight people have been killed and thousands of others displaced after torrential rains poured over the northern Italian region of Emilia Romagna, local authorities said.

The heavy rains caused some 21 rivers to overflow, flooding streets and homes and causing severe disruptions to train traffic, authorities said on Wednesday.

At least 5,000 people have been evacuated from the area, Civil Protection Minister Nello Musumeci said.

The total number of towns hit by the floods are 36, while 48 towns and villages suffered landslides.

Authorities are warning residents in the areas affected that the downpour could continue for another 12 hours.

"The emergency isn't over at all ... the rescue operations are complex and could put the rescuers in danger," Titti Postiglione, deputy head of Italy's Civil Protection Agency, told national broadcaster RAI.

Meanwhile, this weekend’s Imola Formula 1 race, which was scheduled to take place near the worst-hit areas, has been called off.

“The decision has been taken because it is not possible to safely hold the event for our fans, the teams and our personnel,” said the Formula 1 organisers in a statement.

“It would not be right to put further pressure on the local authorities and emergency services at this difficult time,” the statement added.

Two weeks ago, similar weather conditions caused at least two deaths and severe damage in the same region.

Musumeci said the government was closely following the situation and has already earmarked about $10.8 million (10 million euros) for rescue efforts.

Italy has been suffering from prolonged periods of drought in recent years, but experts say other extreme weather events, like storms and floods, are also becoming more frequent due to climate change.

Prolonged drought makes soil less absorbent of rain than usual, increasing the likelihood and severity of floods.