Brazil's president has declared three-days of mourning for the 155 people killed in air crash that may have resulted from a mid-air collision.

Luiz Inacio Lula da Silva expressed sadness Saturday over the loss of passengers and crew in Friday's accident.

Rescue teams located the wreckage of the Boeing 737 in dense jungle in Brazil's Mato Grosso state, about 1,700 kilometers northwest of Sao Paulo.

There are no known survivors.

Authorities say a thorough investigation will be needed to confirm a theory the airliner collided with business jet that made an emergency landing Friday at a Brazilian Air Force base.

None of its passengers were injured.

Gol Airlines flight 1907 disappeared from radar Friday after leaving the city of Manaus in the heart of the Amazon rain forest. Its destination was Brasilia, the capital of Brazil.

Some information for this report provided by Reuters, AFP and AP.