Polls in Iraq are now officially closed for the nation's first free election in nearly 50 years.

Those waiting in line may still cast their ballot.

Iraqis voted in large numbers, defying insurgents who threatened to "wash the streets" with their blood. Some Iraqis said they were casting ballots for a peaceful and free Iraq that will determine its own future.

A national election commission official estimated that 72 percent of eligible voters had cast ballots. But the top U.N. election official in Iraq, Carlos Valenzuela, cautioned it was too early to confirm that figure. But he added turnout had exceeded expectations.

Despite the heavy presence of Iraqi Army, National Guard and police, at least 23 people were killed in a series of attacks. Most were suicide bombings around Baghdad during the first few hours of voting.

An Internet statement attributed to the al-Qaida in Iraq terrorist group led by Iraq's most-wanted fugitive, Abu Musab al-Zarqawi, claimed responsibility for seven of the attacks.

Interim Prime Minister Iyad Allawi, who voted in Baghdad's heavily protected Green Zone, said the election is the start of a new era in Iraq.

More than 5,000 polling stations were open nationwide for the 14 million Iraqis eligible to vote. Final election results are not expected for several days.