SPAIN RECUERS SEARCH UNDERGROUND PARKING AS FRESH FLOODING HITS BARCELONA.(VIDEO/PHOTO).

 Spain rescuers search underground parking as fresh flooding hits Barcelona

The Spanish city of Barcelona has been hit by flooding on Monday, as search and rescue efforts continue following devastating flooding around Valencia last week.

Spain's state meteorological agency has placed parts of Catalonia on red alert for torrential rain, with local media showing footage of cars partially submerged on a highway.

Parts of the Barcelona's El Prat airport, the second largest in the country, have been flooded. More than 80 flights have been cancelled or delayed, while rail services have been suspended.

A similar weather event, which hit the Valencia region with a year's worth of rain last week, has caused at least 217 deaths. On Monday, rescuers focused their efforts on searching for missing people in underground car parks.

The storm caught many victims in their vehicles on roads and in underground spaces, such as car parks, tunnels and garages, where rescue operations are particularly difficult.

It is feared shoppers and workers were trapped inside the car park at a shopping mall in Aldaia, on the outskirts of Valencia, as floodwater overwhelmed the area.

Police have confirmed that no victims were located in the first 50 vehicles inspected at the site.

But reports suggest these vehicles were found near the entrance to the car park, with much of the rest of it still submerged and yet to be explored.

On Monday morning, Spain's interior minister refused to say how many were still missing.

Outside the Bonaire shopping mall in Aldaia, rotting piles of debris lined the roads while noisy generators pumped water from the mall car park.

Spanish police were using drones to get an initial view of the inside, a police spokesperson said.