A Bahraini court jailed 31 people for 15 years on Sunday after convicting them of attacking a police patrol in the Shiite village of Sitra, a lawyer said.
The group was accused of attempted murder and setting a police car ablaze, in addition to rioting and possessing petrol bombs, said the lawyer who requested anonymity.
Fourteen of the defendants remain at large.
Another lawyer said the defendants had denied the charges and claimed that they had been tortured into making confessions.
The interior ministry said in March that police arrested a group of people who attacked a patrol in Sitra with Molotov cocktails, wounding four officers.
Sunni-ruled Bahrain has continued to witness sporadic demonstrations in Shiite-populated villages surrounding the capital Manama after security forces crushed a month-long protest movement in March 2011.
The International Federation for Human Rights says about 80 people have been killed in the Gulf archipelago since the violence first broke out on February 14, 2011.