By Leonardo Benassatto and Debora Ely Reuters

Authorities interrupted rescue efforts in flood-ravaged southern Brazil on Wednesday amid more rain and the risk of lightning and stiff winds that threaten to exacerbate a catastrophe that has already killed at least 100 people and left over 163,000 seeking shelter.

The floods that began last week, caused by unusually heavy rains, have destroyed highways and bridges in the state of Rio Grande do Sul, which borders Uruguay and Argentina.

“We’ve lost everything,” said Adriana Freitas in state capital Porto Alegre, where the Guaiba River burst its banks and inundated city streets. “It’s sad when we see the city, our house, in the middle of the water. It seems like it’s over, that the world has ended.”

At least 128 people are still missing, the state’s civil defense authority said, urging people living close to the Patos lagoon south of Porto Alegre to leave their homes immediately.

Army soldiers used amphibious armored cars to rescue people from flooding in Canoas, just north of the city, where the waters have reached a depth of some three meters (10 ft) and the streets can only be navigated by boat.

A Reuters journalist saw one team of local volunteer rescuers find about 20 dogs stranded on the second floor of an abandoned factory, offering food to those too fierce to take aboard.

Porto Alegre city hall warned such civilian rescuers on Wednesday afternoon to halt their operations, given the forecast for rain, lightning storms and winds exceeding 80 km per hour (50 mph).

In the Porto Alegre suburb of Eldorado do Sul, tractor driver Daniel Farias said he had spent days ferrying survivors to safety, carrying whole families out on his wheel loader, including pets.