Zürcher Nachrichten - At least 18 dead in storms near Rio de Janeiro

"So far, 18 deaths caused by landslides and floods have been confirmed" in recent hours, the Rio de Janeiro Fire Department said in a statement.

The department did not provide figures for those injured or missing.

It said more than 180 firefighters and other rescue workers were at the scene in the picturesque hill town of Petropolis, where Brazil's last emperor Pedro II is buried, 68 kilometers (42 miles) north of the city of Rio.

"Specialized search-and-rescue teams have been sent to reinforce the rescue operations, with the support of 4x4 vehicles and boats," it added.

City hall declared a "state of disaster" as images spread on social media of destroyed houses and cars swept away by floodwater.

Many shops were completely inundated by the rising waters which gushed down the streets of the historic city center.

Some parts of Petropolis received up to 260 millimeters (10 inches) of water in less than six hours, more than was expected for the whole month of February, according to the meteorological agency MetSul.

The heaviest downpour had passed but more moderate rainfall was expected to continue for several hours, authorities said.

Global warming has increased the risk of heavy storms and flooding, as the atmosphere retains more water and rainfall patterns are disrupted.

President Jair Bolsonaro, on an official trip to Russia, said on Twitter that he was keeping abreast of "the tragedy" and asked his ministers to provide "immediate aid to the victims."

Earlier this month, floods and landslides caused by torrential rain killed at least 28 people in the southeast of the country, mostly in Sao Paulo state and the region north of Rio.

In January 2011, more than 900 people died in the mountainous region of Rio due to heavy rains that caused flooding and landslides in a large area including Petropolis and neighboring cities Nova Friburgo and Teresopolis.

Petropolis, the summer residence of the former imperial court, is a tourist destination that attracts a large number of visitors.

Because of its altitude, it has a cooler climate than the coast of Rio.

E.Schneyder--NZN