Baghdad ? Revenge-seeking Shiite militiamen seized six Sunnis as they left Friday prayers, drenched them with kerosene and burned them alive, and Iraqi soldiers did nothing to stop the attack, police and witnesses said.

The fiery slayings in the mainly Sunni neighborhood of Hurriyah were a dramatic escalation of the brutality coursing through the Iraqi capital, coming a day after suspected Sunni insurgents killed 215 people in Baghdad’s main Shiite district with a combination of bombs and mortars.

The attacks culminated Baghdad’s deadliest week of sectarian fighting since the war began more than three years ago.

Police Capt. Jamil Hussein said Iraqi soldiers at a nearby army post failed to intervene in the burnings of Sunnis carried out by suspected members of the Shiite Mahdi Army militia, or in subsequent attacks that torched four Sunni mosques and killed at least 19 other Sunnis, including women and children, in the same northwest Baghdad area.

Imad al-Hasimi, a Sunni elder in Hurriyah, confirmed Hussein’s account. He told Al-Arabiya television he saw people who were soaked in kerosene, then set afire, burning before his eyes.

Two workers at Kazamiyah Hospital said the bodies from the clashes and immolations had been taken to the morgue at their facility. They refused to be identified by name, saying they feared retribution.

In spite of the police and witness accounts, however, President Jamal Talabani appeared to discount the reports. He emerged from meetings with other Iraqi political leaders late Friday and said Defense Minister Abdul-Qader al-Obaidi told him that the Hurriyah neighborhood had been quiet throughout the day.

According to Hussein, the police official, militiamen rampaged through the district, setting fire to several homes in addition to the four mosques that were bombed and burned.

Some residents claimed that the Mahdi Army, the militia loyal to radical anti-American Shiite cleric Muqtada al-Sadr, has begun kidnapping and holding Sunni hostages in order to slaughter them at funerals of Shiite victims of Baghdad’s sectarian violence.

Such claims cannot be verified but speak to the deep fear that grips Baghdad, where retaliation has become a part of daily life.

In the past year, thousands of bodies have been found dumped across Baghdad and other cities in central Iraq, victims who were tortured, then shot to death, according to police. The suspected militia killers often have used electric drills on their captives’ bodies before killing them. The bodies are frequently decapitated.

Burning victims alive, however, introduced a new method of brutality that seemed likely to be reciprocated by the other sect as the Shiites and Sunnis continue killing one another in unprecedented numbers. The attack, which came despite a curfew in Baghdad, capped a day in which at least 87 people were killed or found dead in sectarian violence across Iraq.

The Association of Muslim Scholars, the most influential Sunni organization in Iraq, said even more Sunni victims were killed. It claimed a total of 18 people had died in an inferno at the al-Muhaimin mosque.

The extreme violence continued to tear at the Iraq’s social fabric even after the government had banned pedestrians and cars from the streets and closed the international airport until further notice in anticipation of a storm of retaliation for the five bombings and two mortar rounds that killed 215 in Sadr City on Thursday.

The airport closure forced Talabani to delay his planned Saturday departure for Tehran for meetings with President Mahmoud Ahmadinejad. The Iranian leader also invited Syrian President Bashar Assad, but it now appeared he would not attend.