Guatemala City ? Retired Gen. Efrain Rios Montt, a former military dictator who presided over the bloodiest days of Guatemala’s long civil war, was fighting to regain the presidency in national elections Sunday.

Pre-election polls showed Rios Montt, 77, who took power in a military coup in 1982 and lost it 16 months later in another coup, running third behind former Guatemala City Mayor Oscar Berger and Alvaro Colom, an engineer.

Because of extremely heavy turnout among the country’s 5 million registered voters, election officials extended voting hours indefinitely Sunday night. They said polls would stay open until thousands of voters still in line had a chance to cast ballots. Many voters had waited in line for four hours or longer, partly because of complications with incomplete or inaccurate voter lists.

No candidate is expected to win more than 50 percent of the vote, so the top two finishers will compete in a Dec. 28 runoff. Rios Montt supporters were hoping the polls have underestimated his support among rural voters, who could propel him into the runoff.

At stake is control of the most populous nation in Central America, a largely impoverished and volatile region struggling to establish peaceful, democratic governments after decades of civil wars. An estimated 200,000 people died in Guatemala’s 36-year civil war, which ended with U.N.-brokered peace accords in 1996.

Guatemala is still riddled with government corruption, soaring rates of violent crime and poverty among more than 80 percent of its 11 million people. Wealth and political power is still mainly controlled by a small elite of rich families and their supporters in the military.

As dictator, Rios Montt conducted a “scorched earth” campaign in which villages were burned to the ground in an attempt to wipe out anti-government guerrillas. Exhumations and testimony from survivors have shown that thousands of people were executed, raped and burned alive during his tenure.

More than 1,000 residents of 23 affected villages have filed a genocide case against Rios Montt in a Guatemalan court. Rios Montt has been immune from prosecution because he has remained president of the Guatemalan Congress. If he does not win the presidency, his immunity ends when his term ends in January.

Maria Fidelina Tubac, 29, left, waits in line to vote with her daughter in San Juan Comalapa, Guatemala. So many Guatemalan residents came to polls in Sunday's presidential elections that voting was extended indefinitely until lines could be cleared.