Heavy rain has caused flooding and landslides that have killed 36 people in Brazil's north São Paulo state, with the fatalities expected to rise.

São Paulo's state government said in a statement that 35 died in the city of São Sebastião and a 7-year-old girl was killed in neighbouring Ubatuba.

The cities of São Sebastião, Ubatuba, Ilhabela and Bertioga, some of the hardest hit and now under a state of calamity, cancelled their Carnival festivities as rescue teams struggle to find missing, injured and people feared dead in the rubble.

"Our rescue teams are not managing to get to several locations; it is a chaotic situation," said Felipe Augusto, the mayor of São Sebastião.

Later, he added that there were dozens of people missing and that 50 houses collapsed in the city due to the landslides.

Mr Augusto posted on social media several videos of widespread destruction in his city, including one of a baby being rescued by locals lined up on a flooded street.

Brazil's President Luiz Inácio Lula da Silva said on Twitter he would visit the region on Monday.

The São Paulo state government said in a statement that precipitation in the region had surpassed 600 millimetres in one day, one of the highest amounts ever in Brazil in such a short period.

Bertioga alone had 687 millimetres during that period, the state government said.

Governor Tarcísio de Freitas said in a statement he requested support from the army, which sent two aeroplanes and rescue teams to the region.

TV footage showed houses flooded with only the roof visible.

Residents are using small boats to carry items and people to higher positions. A road that connects Rio de Janeiro to the port city of Santos was blocked by landslides and floodwaters.

The northern coast of São Paulo state is a frequent Carnival destination for wealthy tourists who prefer to stay away from massive street parties in big cities.

AP