Bahrain has sentenced eight people to life in prison for their part in the killing of a policeman in a bomb blast last November.
The country's Supreme Criminal Court said the eight men planted a homemade bomb close to a police checkpoint which killed one police officer and injured four others.
The defendants were accused of luring policemen to the area by setting tyres on fire and blocking the road in the attack.
Bahrain's main opposition group, al-Wefaq, said on its website that the detainees were regularly subjected to torture and forced to make confessions.
The group also accused the courts of ignoring human rights violations committed by security forces.
The Bahrain government says it has taken steps to address security forces' violations by dismissing those responsible, but activists say this has not helped.
The Kingdom's Shia majority have long complained of under-representation and discrimination, a claim the government denies.
Bahrain has experienced unrest since 2011, with a Shia-dominated opposition movement demanding greater political rights from the Sunni monarchy.
The protests which were heavily put down by the authorities, have given rise to regular low-level violence by demonstrators against security forces.
Previous rounds of reconciliation have failed with the opposition demanding amnesty for what they claim are more than 3,000 political prisoners held in jails.