Bahrain has gone to the polls for its first legislative elections since 2011, with the opposition boycotting the vote in the tiny Gulf monarchy.
However, voting at the polling centres was extended by two hours due to the large turnout.
The key US ally remains divided nearly four years after security forces in the Sunni Muslim-ruled kingdom crushed Arab Spring-inspired protests led by majority Shi'ites.
Al-Wefaq, the main opposition group, warned on the eve of the vote that failure by the kingdom's rulers to ease their "monopoly" on power could trigger a surge in violence.
Clashes between young demonstrators and security forces erupted in Shi'ite villages outside the capital, Manama, before the polls, according to witnesses.
Bahrain's electorate of almost 350,000 is being called to choose 40 deputies. Most of the 266 candidates are Sunnis in a vote denounced by critics as a "farce".
The boycott means turnout will be seen to be a key marker of the validity of the vote.
The opposition wants a "real" constitutional monarchy with an elected prime minister independent from the al-Khalifa royal family.
But the Saudi-backed Sunni dynasty that rules over the majority Shi'ite kingdom has rejected the demand.
