State television said the security chiefs arrived Saturday afternoon at parliament, where they will be questioned during the session.
Abbas al-Bayati, the head of parliament's defense committee, said the lawmakers are expected to ask the ministers of interior and defense how suicide bombers managed to elude security Tuesday in heavily guarded downtown Baghdad.
He added they will also be asked about what precautions are being taken to prevent future attacks.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
BAGHDAD (AP) - Amnesty International on Friday warned that Iraq's plans to move an Iranian opposition group to a former desert detention camp in the country's remote south would put them at risk of arbitrary arrest and torture.
Iraq's Shiite-led government has taken an increasingly hard line toward the People's Mujahedeen Organization of Iran, not wanting to risk its warming relations with its powerful Shiite neighbor Iran.
The exiles had been hosted for years by Saddam Hussein, who allowed the Iranians to establish a base for launching raids into Iran during the two neighbors' eight-year war. After the U.S.-led invasion in 2003, the group was put under watch.
Iraq announced plans Thursday to move the roughly 3,500 residents from their camp in northeastern Iraq to the desert south. In July, Iraqi security forces raided Camp Ashraf and touched off riots that killed 11 people.
Amnesty International said it feared the "forced removals of the residents of Camp Ashraf would put them at risk of arbitrary arrest, torture or other forms of ill-treatment and unlawful killing."
The Iraqi plan calls for moving the exiles to a remote outpost in Neqrat al-Salman, about 200 miles (120 kilometers) west of the southern city of Basra. It was used for decades as a detention center where Saddam banished political opponents.
"Whatever measures the Iraqi authorities decide to take with regard to the future of Camp Ashraf, the rights of all its residents must be protected and guaranteed at all times," said Hassiba Hadj Sahraoui, a deputy director with Amnesty International.
The U.S., which has listed the People's Mujahedeen as a terrorist organization, has expressed concern that moving the group could result in violence.