RIO DE JANEIRO -- Brazilian President Jair Bolsonaro on Wednesday visited the state of Acre, in the Amazon rainforest, where several cities have been submerged in floodwaters, adding yet another challenge for the beleaguered state.

Several rivers overflowed their banks due to extreme rainfall. Overall, 120,000 people have been displaced as a result of flooding, according to data from the state's fire department, and federal authorities have declared a state of calamity in ten municipalities.

In Sena Madureira, one of the worst-hit cities, nearly 70% of its area was either submerged or affected by the floods, with more than 4,000 families relocated, the fire department said.

In Rio Branco, Acre's capital, televised images showed large swaths of the city flooded.

Water levels in several municipalities were falling on Wednesday, but more rain is expected this week.

The floods pose more hardship for the impoverished state that was already battling with a resurgence of COVID-19, an outbreak of dengue fever and a migratory crisis at its border with Peru.

Acre confirmed 622 new cases of COVID-19 on Tuesday, according to Health Ministry data.

Gov. Gladson Cameli said Tuesday that he had requested that more oxygen be dispatched to Acre in order to treat the rising number of patients and to avoid a public health disaster like that of neighbouring Amazonas state. Earlier this year, hospitals' oxygen ran out in Amazonas' capital, Manaus, forcing patients' families to scramble to find cylinders on their own.

"I will not be caught off guard by someone's death because I didn't have oxygen," Cameli said.

The state has also suffered more than 10,000 suspected cases of dengue in the first two months of this year, more than double the amount in the same period in 2021, according to online news site G1. Cameli warned that once rivers' water levels recede, dengue and other mosquito-borne diseases are likely to spread more aggressively, increasing pressure on the public health system.

"I'm asking that professionals who are able come here to give us a hand," he said.

Finally, authorities have to deal with a lingering migratory crisis at its border with Peru. Some 400 migrants arrived at Acre's border town of Assis Brasil in mid-December.

Migrants, mostly Haitians and Venezuelans, have been trying to cross the border into Peru on their way to Mexico and the U.S, federal authorities said. But the Peruvian government closed its border with Brazil last year, due to the COVID-19 crisis.

Brazil's citizenship minister, Miguel Angelo Oliveira, said that the migrants were wrongly informed that the border in Assis Brasil had reopened. Clashes between migrants and Peruvian police forces erupted last week.