THE WORLD - Rivalry among Sunni militants explodes into war in Samarra

The deadline passed and then the war began in Samarra.

Islamic Army member Abu Ibrahim remembers the fateful meeting in September, and the recriminations between his group and the umbrella group Islamic State of Iraq, which ended years of collaboration in a city that had proved impossible for the Americans to tame.

"After the week, they said that they will kill us because, as they say, you are either with us or against us," Abu Ibrahim recalled Saturday.

Since then, dozens have died in the internecine Sunni bloodletting in Samarra, the city 75 miles north of Baghdad where nearly two years ago Sunni insurgents blew up a revered Shiite shrine, broadening the civil war.

On Friday, Abu Ibrahim said, the two sides had their fiercest battle yet in a district 10 miles southeast of Samarra. The three-hour battle ended with 18 Al Qaeda in Iraq fighters dead, including their local leader, he said.

Abu Ibrahim claimed that his group captured 16 fighters and herded them back to the Islamic Army's secret prisons. Five of his own men were killed, he said.

The battle between the two Sunni groups, both committed to killing Americans, fits into a broader trend of Sunni revolt against groups linked to Al Qaeda in Iraq.

But the Samarra conflict arguably has less to do with the U.S. war than with Sunni feuds and power struggles. It also shows how even as groups across Iraq break with Al Qaeda in Iraq, civilians are still at the mercy of gunmen.

Since that meeting in September, the factional fighting has made Samarra's nightmarish situation even worse. A third party is also in the mix -- Iraq's controversial national police, a force that has been accused of regularly using excessive violence. Its Samarra branch is under the supervision of Rashid Flaih Mohammed, a Shiite general who was removed in fall 2006 from a similar job in Baghdad amid allegations that his troops were involved in sectarian attacks.

A string of killings and kidnappings by the two insurgent factions has left Samarra a minefield.

"It is very sad to see the sons of our city fight each other under any condition," said Iyad Awad, 28, a machinist. "The killer and the victim are from the city."