Iraq's National Security advisor says authorities have arrested a key al-Qaida suspect in connection with the bombing of a Shi'ite shrine that triggered sectarian violence earlier this year.

Iraqi National Security Adviser Mouwafak al-Rubaie

Mowaffaq al-Rubaie said in Baghdad Wednesday that the Tunisian suspect, known as Abu Qudama, was wounded in a clash with Iraqi and U.S. troops a few days ago.

He said the man confessed to the bombing of the centuries old Golden Dome shrine in the northern town of Samarra on February 22. But Rubaie said the suspected ringleader of the plot is still on the run.

In new violence, a car bomb killed three people near a Sunni mosque northeast of Baghdad. A roadside bomb killed another Iraqi near the capital.

In another development, Iraqi Prime Miniser Nouri al-Maliki said Wednesday several insurgent groups have contacted him to discuss amnesty as part of his national reconciliation plan. He added that militants involved in the killing of U.S.-led troops will not be eligible.

On Tuesday in Washington, the U.S. general in charge of training Iraq's new security forces said the new Iraqi army will be fully in place by the end of the year.

But he said the Iraqi army, police and the ministries that support them will need additional time to function effectively so that the country will not need foreign forces.