A sudden rainstorm and hailstones hit Beijing on Wednesday afternoon, submerging 18 vehicles parked on a low road, but no casualties have been reported, the municipal flood control office said on Thursday.

The northwestern districts and suburbs witnessed the most rain, in which the heaviest rainfall reached around 50 millimeters an hour in Haidian district. Hailstones hit Changping district around 6 pm on Wednesday.

Economic losses due to the storm were around 5 million yuan ($806,020), the municipal flood control office said.

The Haidian district government said a road under the flyover at Tiancun East Road flooded after tree branches blocked drainage holes, making the floodwater rise quickly and inundating 18 parked cars.

Insurance companies have started investigations for future claims, the district government said.

The capital has taken efforts to increase its flood control ability to avoid deaths since a rainstorm hit Beijing on July 21, 2012, killing 79 residents.

Major flyovers in downtown areas, which are prone to flooding, have been improved with more powerful pumps, aiming to drain water quickly and protect cars from being submerged.