An armed man is holding a number of passengers hostage on a commuter bus in the Brazilian city of Rio de Janeiro, Report informs citing BBC.
The incident occrred in the morning on the bridge Rio-Niteroi.
Traffic on the bridge has been blocked completely.
Military police officers, ambulances and a special operations team are at the scene.
At least five passengers have been freed. More than a dozen are still believed to be on board.
Brazilian media say it is not clear if the armed man has made any demands. He reportedly boarded the bus at 05:30 (0830 GMT) and threatened passengers.
Traffic on the bridge has been blocked completely.
Police say they are speaking to the hijacker who motives are yet unclear.