BAGHDAD - Iraq's prime minister said Saturday that the government has defeated terrorism in the country, a sign of growing confidence after recent crackdowns against Sunni extremists and Shiite militias.

Prime Minister Nouri al-Maliki launched the crackdowns to extend the authority of the government over areas in Baghdad and elsewhere that have largely been under the control of armed groups since the U.S.-led invasion in 2003.

"They were intending to besiege Baghdad and control it," al-Maliki said. "But thanks to the will of the tribes, security forces, army and all Iraqis, we defeated them."

He was speaking at ceremonies marking the fifth anniversary of the assassination of Ayatollah Mohammed Baqir al-Hakim, a leading opponent of Saddam Hussein who was killed in a bombing in the southern Iraqi city of Najaf after returning from exile in Iran.

Such attacks plagued Iraq following the U.S.-led invasion, but violence in the country has now fallen to its lowest level in four years.

"Under the national unity government, the Iraqis have achieved national feats ... that are now lighting the course of our march," al-Maliki said.

Iraq is also enjoying a surge in oil revenue driven by record crude prices and the highest production levels since Saddam's ouster.

Despite recent gains, daily attacks continue throughout Iraq.