Heavy rain began lashing Bahía Blanca in Buenos Aires province at about 04:00 local time, turning streets into rivers and leaving large parts of the city without electricity.

At a local hospital, new-born babies had to be evacuated after flood waters invaded the building. Elsewhere, more than 40 families have had to leave their homes and the airport has been closed. Local authorities closed schools and suspended public transport. They warned residents to stay at home until further notice.

The authorities said up to 250 millimeters (10 inch) of rain had already fallen, with another 50-100 millimeters expected before the storm abates.The city normally receives about 600-650 millimeters of rain a year. Images shared on social media showed cars being carried off by raging flood waters.

"Due to the climate emergency and in order to protect the safety of residents, the Municipality of Bahía Blanca orders the absolute cessation of all types of activities until further notice," local officials said. Bahía Blanca is under a state of emergency and the authorities have opened several evacuation centres in different parts of the city.

Bahía Blanca, a city with about a third of a million inhabitants, is a major port in the south-western part of Buenos Aires province.