Early voting began Thursday morning in Iraq's parliamentary election, which will elect a government that will guide the country as U.S. forces go home and help determine whether Iraq can overcome the deep sectarian problems that have divided it.

Hundreds of thousands of Iraqis are expected to take part in early voting, a one-day session designed for those who might not be able to get to the polls Sunday, when the rest of the country votes.

Early voters include detainees, hospital patients and military and security personnel who will be working election day.

An electoral official in the Independent High Electoral Commission, Karim al-Tamimi, said: "The special voting has started and the turnout is good. The process is going smoothly and safely."

The United Nations Assistance Mission to Iraq estimated that between 600,000 and 700,000 people could vote Thursday. About 19 million voters in total are eligible to take part in the elections, which will also take place in 16 countries around the world.

These are only Iraq's second elections for a full parliamentary term since the U.S.-led invasion in 2003 ousted Saddam Hussein, leading to the eventual creation of the Shiite-dominated government in power today.

Security is expected to be extremely tight Thursday with officials in the western province of Anbar already announcing a vehicle ban on Thursday morning.

Around the country, hundreds of thousands of police and military have been flooding the streets to prevent attacks by insurgents who have warned they would try to disrupt the vote. The Baghdad airport is slated to be closed election day.

In the city of Baqouba, suicide bombers killed at least 32 people Wednesday in a series of three bomb attacks that officials there said were intended to dissuade people from voting.