The public outburst illustrates the intense sectarian tensions in the country and could renew calls by Shiite politicians that Adnan al-Dulaimi, the Sunni politician in question, be stripped of his parliamentary immunity to stand trial for inciting sectarian strife.
The quarrel began when Bahaa al-Aaraji, a follower of radical Shiite cleric Muqtada al-Sadr, told the 275-seat house that he had evidence that al-Dulaimi has branded Shiites "heretics" whose killing is legitimate.
He said the evidence was in documents he held while addressing parliament, but declined to divulge their contents when he later spoke to reporters.
"Legal action must be taken against him," he said over al-Dulaimi's protestations.
"They are false, they are false," the Sunni Arab politician shouted.
Speaker Mahmoud al-Mashhadani instructed al-Aaraji to submit the documents to the parliamentary Security and Defense Committee. Its chairman, Hadi al-Amri, later said that parliament would be willing to lift al-Dulaimi's immunity if the judiciary requests it.
Al-Mashhdani is a Sunni Arab and a member of the Iraqi Accordance Front, the three-party alliance that has 44 parliamentary seats and is led by al-Dulaimi.
Al-Amri is a member of the country's most powerful Shiite party and is thought to have led its affiliated militia, the Badr Brigade, until recently.' continued