A man armed with a gun, knife and a can of gasoline took at least 37 people hostage on a public bus early Tuesday in Brazil before being fatally shot by police, authorities said.

Federal Highway Police said the man had been holding passengers hostage since about 5:30 a.m. local time on a bridge connecting the suburb of Sao Gonçalo to Rio de Janeiro. He was threatening to set the bus on fire.

Rio's elite police force, known as BOPE, handled negotiations with the kidnapper. A sniper was ready nearby.

The man released six hostages in the first few hours, authorities said. According to Brazilian newspaper O Dia, Federal Highway Police spokeswoman Sheila Sena told TV Globo that the man identified himself as a military police officer and was armed with a gun and gasoline.

Hans Moreno, one of the hostages, said on TV Globo that the man was "very calm."

Authorities said the man did not make any specific demands and may have had "psychological problems."

As a result of the kidnapping, traffic toward Rio de Janeiro was shut down, O Dia reported. One van caught in the mess was carrying patients headed to Rio for medical procedures, according to O Dia.

Marinete Oliveira da Silva, who was traveling to Rio for surgery for a head tumor, told O Dia that she was very shaken up.

Contributing: Associated Press

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