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The condition of some of the injured passengers are stated to be critical.
The crash occurred on the Jessore-Jhenaidah highway on Tuesday afternoon, said police.
Kotwali Police Station Sub Inspector Yousuf Ali said the Kushtia-bound bus lost control while overtaking a truck.
He said five died on the spot.
The injured people were admitted to Jessore Sadar Hospital where another victim died while undergoing treatment, said Sub-Inspector Babul Chandra Roy at the hospital police camp.
The Fire Service said all of the victims were passengers of the bus.
Five of the deceased have been identified as Arabindu Roy and his wife Eti Rani Roy, Rizia Khatun, Ram Prasad, and Enamul Haque.