U.S. and Iraqi soldiers captured six members of an alleged "death squad" in Baghdad on Tuesday, hoping to quell the rampant sectarian violence dividing the capital, while attacks elsewhere in Iraq left at least 26 people dead.

In Washington, President Bush met Prime Minister Nouri al-Maliki at the White House to discuss the deteriorating security situation. Bush said a U.S. military program to bolster Iraqi security forces in Baghdad will better address the violence there as he pledged to stand by Iraq's new democratic government.

"He believes and I believe that there needs to be more forces inside Baghdad who are willing to hold people to account," Bush said during a joint news conference.

Al-Maliki said the most important element of a new security program "is to curb the religious violence."

Representatives of Iraq's ethnic and sectarian groups met in Cairo, Egypt, to discuss ways to reconcile. Some 30 delegates representing Shiites, Sunnis, Kurds and other smaller minorities participated in discussions sponsored by the Cairo-based Arab League.

The talks are intended to prepare for a national reconciliation conference in Baghdad next month. U.S. officials believe control of Baghdad — the political, cultural, transport and economic hub of the country — will determine the future of Iraq.

"This is a duty for Iraqis to find out ways for ending this dilemma," said Arab League Undersecretary-General Ahmed Ben Heli, whose group sponsored the conference.

The six suspects, including a cell leader, were detained during a pre-dawn raid on four buildings in Baghdad, a U.S. military statement said. It was not clear if those detained Tuesday were Sunnis or Shiites.

Later in the day, gunmen attacked a police checkpoint in Dujail, about 50 miles north of Baghdad, and ambushed a sport utility vehicle belonging to a private security company in north Baghdad, killing eight people.

The killings gripping the capital accelerated after the Feb. 22 bombing of a Shiite shrine in Samarra and have steadily increased despite the establishment of al-Maliki's national unity government in May.

"We are determined to defeat terrorism and the security plan for Baghdad has entered the second phase, and it's achieving its objectives in hunting the terrorists and networks, and eliminating it," al-Maliki said in Washington.

Many of the death squads are believed to be associated with either Sunni or Shiite armed groups, targeting rival sect members as part of a struggle for power between the country's two major religious communities.

U.S. officials have avoided identifying death squads and militias by sect, preferring instead to refer to them as criminals and thugs. Iraq's army and police, which are heavily Shiite, have had trouble winning the trust of residents of majority Sunni neighborhoods.

As a result, the top U.S. commander in Iraq, Gen. George W. Casey Jr., has said more American troops will take to the streets to bolster Iraqi forces, especially in Sunni areas such as Dora, Amariya and Ghazaliyah.

In other violence Tuesday, the head of Saddam Hussein's tribe was killed when gunmen attacked a meeting in the office of a prominent sheik in Tikrit.

Mahmoud Ali Hussein al-Nida, head of the Baijat tribe, died following the attack at about 7:30 p.m. Monday. The gunmen also killed a lawyer and wounded sheik Mizahim al-Mustafa, police Lt. Ahmed Asaad said. Two other civilians caught in the crossfire also were killed, Asaad said.

The Baijat tribe includes several clans, including Saddam's Albu-Nassir clan. Al-Nida was not directly related to Saddam.

In northeastern Baghdad, a suicide car bomber attacked a joint Iraqi-U.S. checkpoint, killing three.

At least 11 bullet-riddled bodies were found dumped in two Baghdad neighborhoods, police said.

U.S. military commanders have struggled to quell the violence and have only recently intensified their efforts to disrupt groups of Sunni gunmen and Shiite militias responsible for much of the violence.

Last week, U.S. and Iraqi forces conducted 19 operations specifically targeting death squads. All but two were in Baghdad.

"Clearly Baghdad is the center that everybody is fighting for," Maj. Gen. William Caldwell, spokesman for the U.S. military in Baghdad, said this week. "We will do whatever it takes to bring security to Baghdad."

In other violence, a parked car bomb near a police checkpoint in southern Baghdad's Rissala neighborhood in Baghdad's Abu Ghraib suburb exploded at 4:45 p.m., injuring five civilians, police said.

Five bodies were found in the streets of Muqdadiyah, about 60 miles north of Baghdad, in Diyala province.