Clashes erupted Monday in Iraq's holy city of Karbala, as Shi'ite pilgrims streamed into the city for a major religious festival expected to be attended by more than one million people.

Officials say three people were killed and 13 wounded, as pilgrims angry over strict security measures battled with police.

Authorities also say gunmen in Baghdad shot and killed a Shi'ite pilgrim heading to Karbala, which is south of the Iraqi capital.

The festival Tuesday marks the birth of Mohammed al-Mahdi, the 12th and last Shi'ite imam.

Meanwhile, in Fallujah, police say a suicide bomber killed at least nine people and wounded at least 10 others in an attack on a mosque during evening prayers.

On the political front, Sunni politicians refused to end their boycott of Iraq's coalition government, despite a deal by Iraqi factions to resolve key issues to boost national reconciliation.

The politicians praised the deal, which was announced Sunday, but said they will not return until reforms are made.

Iraq's largest Sunni Arab political bloc, the Sunni Accordance Front withdrew from Iraq's Shi'ite-majority government earlier this month, saying it had failed to meet its demands. The demands included dealing with Shi'ite militias and reforming Iraqi security forces and detention procedures.

In other news, the U.S. television network CBS says one of its translators was found dead in Iraq after being abducted by insurgents. The network says Anwar Abbas Lafta was the third CBS employee to be killed in the Iraq war.

The U.S. military says coalition forces killed eight terrorists in operations targeting al-Qaida in Iraq. A statement says troops detained 16 suspects in raids in central and northern Iraq.

The military also announced the combat deaths of four U.S. service members.

Some information for this report was provided by AFP, AP and Reuters.