Baghdad, Iraq ? Suicide bombers killed 13 people in a pair of attacks Monday around the Sunni Arab city of Ramadi in what local officials said was part of a power struggle between al-Qaida and tribes that have broken with the terror network.

In all, at least 68 people were killed or found dead nationwide Monday, police said. They included the bullet-riddled bodies of 30 men found in Baghdad – the apparent victims of sectarian death squads.

All but two were found in west Baghdad, including 17 in the Amil neighborhood where Sunni politicians have complained of renewed attacks by Shiite militiamen, said a police official who spoke on condition of anonymity because he was not supposed to release those details.

Sunni complaints prompted the country’s Sunni vice president to threaten to leave the Shiite-dominated government unless key unspecified amendments to the constitution are not made by May 15.

The power struggle among the Sunnis, which surfaced last year, could prove decisive in the U.S. campaign to win over significant portions of the Sunni community, which has formed the bedrock of the insurgency.

The first of the Ramadi area attacks happened about noon in a market on the northwest outskirts of the city, killing eight people and wounding 13, said police Col. Tariq Youssef.

About 15 minutes later, police at a nearby checkpoint spotted a second car bomb and opened fire, but the driver was able to detonate the vehicle, Youssef said. Five people, including two policemen, were killed and 12 were wounded, Youssef said.

The attacks occurred in areas controlled by the Anbar Salvation Council, an alliance of Sunni tribes formed last year to drive al-Qaida from the area. Council officials blamed the attacks on al-Qaida.

In a Web statement Monday, an al-Qaida front organization, the Islamic State of Iraq, warned Sunnis against joining the government security forces – a move supported by the Salvation Council.

The Islamic State also claimed responsibility Monday for attacks that killed 34 people over the weekend – including six U.S. soldiers and a Russian embedded photojournalist who died in a roadside bombing in Baqouba.

The security situation in the capital figured high in talks between Prime Minister Nouri al-Maliki and President Bush, who conferred Monday in a video conference.

Al-Maliki told Bush of the need to maintain cooperation between U.S. and Iraqi forces as they continue their campaign to end the chaos and violence in Baghdad, the prime minister’s office said in a statement.