The interior ministry of the Gulf state had announced on Twitter yesterday the death of the 45-year-old, saying he died while exercising at Jaw prison south of Manama.
It attributed Mohammed Sahwan's death to natural causes, but relatives claimed he died as a result of injuries sustained during the crackdown in 2011 of the Shiite protest movement calling for reforms to the Sunni monarchy.
His relatives said Sahwan's head and body still contained buckshot from injuries sustained during the protests six years ago.
Police fired buckshot and tear gas to disperse them, the witnesses said.
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