RIO DE JANEIRO (AFP) - Two Brazilian ferry wrecks in as many days left at least 43 people dead, authorities said on Thursday (Aug 24), as rescuers searched for several more who were still missing.

"We deeply regret the loss of tens of lives in the boat accidents in Para and Bahia," two states in the north of the country, President Michel Temer said on Twitter.

Regional authorities in north-central Para state said 21 people were confirmed dead so far after a boat sank on the Xingu river late Tuesday.

That vessel, the Capitan Ribeiro, had 49 people on board, of whom 23 were rescued.

Emergency teams were still searching for five more, the department said in a statement.

Separately, the navy said 22 people died when a ferry sank early Thursday off the northeastern state of Bahia.

That boat had 133 people on board, of which at least 21 had been rescued, naval commander Flavio Almeida told AFP.

The vessel was running the short route from the island of Itaparica across the bay to the city of Salvador, capital of Bahia state, when it went down in a storm.

"It was raining... a wave came and the boat turned over. There were a lot of people" on board, one survivor, Edvaldo Santos de Almeida, told top news website G1.

He said scores of military personnel were working on rescue efforts at the site.

The state government decreed three days of mourning.

"I have been personally following this difficult operation from an early stage and all measures have been taken immediately," said Bahia governor Rui Costa.

SEARCH FOR SURVIVORS

In the incident in Para, in a northern Amazon region, survivors told local media that the boat got caught in a rainstorm.

The vessel had left the port of Santarem bound for Vitoria de Xingu.

The regional public safety department gave a toll of 19 in a statement early Thursday.

The department later told AFP that two further bodies had been found, bringing the total to 21.

Rescuers were searching for the missing in the Xingu river.

"It's a hard-to-access area," Colonel Augusto Lima, from the Para firefighters' service, was quoted as saying on Wednesday by the newspaper Folha de Sao Paulo.

The victims who were rescued got out by swimming, Globo news reported, saying the boat went down about 500 meters from the riverbank.

Ferries, fishing vessels and big commercial ships ply the Amazon waterways as one of the main forms of transport in a region with relatively few roads.

Some 1,160 people have been killed in accidents on rivers in the Amazon since 1981, according to Folha.