Foreign Minister Hoshyar Zebari urged Iraq's neighbors Sunday to prevent "terrorists and killers" from crossing into his country and warned that the violence in Iraq could spill across its borders into other nations.

Zebari's comments came during the opening of a daylong conference that brought to Baghdad officials from all of Iraq's neighbors and other Mideast countries, as well as representatives from the U.N. and the Group of Eight industrialized nations.

It picked up from the first such conference in March, which saw the first direct U.S.-Iranian talks since the war began, focusing on border problems, Iraqi refugees and energy issues, including oil supplies.

"Despite our emphasis on national reconciliation at home we also need to reconcile with our neighborhood, with the international community at large," Zebari told the group. "And this is critical period for us that we need your support and your commitment especially for our immediate neighbors."

Elsewhere, the U.S. command said a Marine died in Iraq's Anbar province in a non-combat related incident. The Marine, with the Multinational Force-West, died Friday in an incident that is currently under investigation, the military said.

In northern Iraq, U.S. forces killed one of the insurgents suspected to be behind the quadruple suicide bombings in August against communities of Yazidis, a Kurdish-speaking religious minority, that killed 520 people, U.S. military spokesman Rear Admiral Mark Fox said.

Abu Muhammad al-Afri, an Al Qaeda in Iraq regional leader also known by several pseudonyms, was killed in an airstrike on Sept. 3 southwest of Mosul, Fox said.

Zebari's appeal to Iraq's neighbors occurred on the eve of the start of congressional hearings in Washington by U.S. Ambassador to Iraq Ryan Crocker and top commander Gen. David Petraeus who are to deliver key reports on Iraq's progress amid a debate over calls to start bringing American troops home.

Iraqi government spokesman Ali al-Dabbagh said he there has been "progress on the security side, particularly in Baghdad," but said support from the U.S. was still needed and that there should be no timetable set for it to end.

"When things get better and the security situation gets better the Iraqi government will be able to talk about a timetable," he told a regular news conference.

U.S. officials have also said security has been improving but that they are not seeing significant progress politically with Prime Minister Nouri al-Maliki's government.

But al-Maliki disputed that assessment at the meeting Sunday, saying the "Iraqi national unity government has achieved great victories in different fields as it works seriously to improve the economic situation, and has achieved major results despite the major economic destruction that we inherited from the former regime."

Security was extraordinarily tight in central Baghdad where the meeting was taking place at the Foreign Ministry complex with security forces blocking two main bridges linking the city's eastern and western sectors to all but official traffic.

Parliament canceled its session Sunday for lack of a quorum because many legislators could not make it due to the closed roads, said Wissam al-Zubaidi, an adviser to deputy parliament speaker Khaled al-Attiyah.

The Iranian and Syrian deputy foreign ministers headed their countries' delegations while other regional countries were represented by their ambassadors, Zebari told the AP ahead of the meeting. In addition to neighbors Turkey, Saudia Arabia, Kuwait and Jordan, delegations from Egypt and Bahrain were present.

With Crocker in Washington, the U.S. was represented by the deputy chief of mission in Iraq, Patricia Butenis.

Zebari said they needed to talk about helping the Iraqi government bring security and stability to Iraq internally, but added that the country's neighbors needed to "actively work on controlling the borders and prevent terrorists and killers from infiltrating across into Iraq."

"Terrorism should be fought ... because the fires that they are igniting in the land of the two rivers (Iraq) will spread outside the borders and endanger neighboring countries," Zebari said.

He did not identify any country by name, but the Iraqi and U.S. governments have accused Syria of allowing foreign fighters to cross into Iraq and say Iran is supplying Shiite militias with weapons — claims that both countries deny. The Iraqi government has also said that many of those who carry out suicide attacks in Iraq come from Saudi Arabia.

Though violence has been slowed by the U.S. buildup in troops from the start of the year, sectarian and insurgent attacks are still common.

On Sunday morning in Baghdad two mortar rounds landed in a predominantly Shiite area killing one person and injuring nine others, according to police.

About 30 kilometers (20 miles) south of the city in Mahmoudiya, a booby-trapped minibus exploded near a courthouse, killing one civilian and wounding five others, police said.

In the southern city of Diwaniyah, unknown assailants gunned down Sheik Hassan al-Aswad, a leading figure in the shadowy armed cell called the Soldiers of Heaven, or Jund al-Samaa, police said.

The group was involved in a fierce gunbattle earlier this year with Iraqi forces who accused it of planning to kill Shiite clerics and others in the belief it would hasten the return of the "Hidden Imam" — a descendant of the Prophet Muhammad who disappeared as a child in the 9th century. Shiites believe he will return one day to bring justice.

Al-Aswad had been in custody but was freed a few days ago, police said.

Meanwhile, scores of gunmen raided a police station in predominantly Sunni village in northern Iraq, killing six policemen before they were driven off with the help of residents, police and eyewitnesses said.

The attackers drove in 10 vehicles from the west into Hajaj, some 250 kilometers (155 miles) north of Baghdad, and opened fire on the police station at about 10 a.m., according to an eyewitness who spoke on condition of anonymity out of security concerns.

Most of the police were residents, and villagers rushed to their support in the gunbattle that ensued. One resident said 80 attackers were involved.

Footage from Associated Press Television News of the aftermath of the attack showed a tattered Iraqi flag fluttering in the wind from the one remaining corner of the police station. One of the white pickup trucks used by the attackers, and badly damaged, remained at the scene next to a pile of the rubble of the police station.

Authorities said six policemen were killed but there were no immediate reports of casualties among the villagers or attackers.