A Bahrain court sentenced 17 people to 15 years in prison on Sunday after convicting them of trying to kill four policemen with a homemade bomb during political unrest last year.
The attackers planted the bomb in a roadblock formed of tyres, palm tree trunks and garbage bins, and detonated it when a police patrol approached, state news agency BNA quoted prosecutor Mamdouh Al-Maawda as saying.
The four policemen were seriously hurt and burned during the attack in April 2012, BNA reported.
The tiny island kingdom has been plagued by sometimes violent street protests since pro-democracy protests led by its Shi'ite Muslim majority erupted in early 2011.
Also on Sunday, a group of people attacked a diesel tanker with Molotov cocktails, BNA quoted police as saying. Civil defence personnel extinguished the flames before they reached the diesel cargo.