KIRKUK, IRAQ — American officials, regional leaders and residents are increasingly worried that this northern oil-rich city could develop into a third front in the country's civil war just as additional U.S. troops arrive in Baghdad and Al Anbar province as reinforcements for battles there.
Al Qaeda-linked fighters recently have surfaced here, launching a wave of lethal attacks, U.S. and Iraqi officials say. The attacks come amid a rise in communal tensions in the months before a referendum on the status of the city and the surrounding province.
Elsewhere in Iraq, Shiite and Sunni Arab Muslims are locked in a bitter civil war. Here, the two groups have a common cause against the Kurds, a non-Arab minority that dominates Iraq's far-northern provinces.
The Kurds, Arabs and Turkmens, another minority group, each want control of this city and the region. At stake are land, water and some of Iraq's richest oil reserves.
None of the groups want war, they say. Yet everyone here appears to be preparing for it.
"They are right when they call it a time bomb," said Sheik Abdul Rahman Obeidi, a prominent Sunni Arab leader in Kirkuk. "We will not leave, and we will not let anyone take Kirkuk. We are ready to fight. We hope we won't have to, but we're ready."
Kurdish leaders, in turn, warn that they will take the city by law or by force.
"People don't have any more patience," said Kurdish Councilman Rebwar Faiq Talabani, sitting in Kirkuk's heavily fortified provincial council building. "They are telling the government, 'If you can't get our rights back, we'll do it by ourselves.' "
Neighboring countries, especially Turkey and Iran, fear that if the Kurds do gain control of Kirkuk, Iraq's semiautonomous Kurdish region would have the confidence and economic power to move toward independence. That could embolden Kurdish militants in the surrounding countries and further destabilize the region. Turkish officials recently have threatened to intervene if the Kurds take over Kirkuk and have warned against efforts to change the city's population balance.
"Turkey cannot stand idly by, watching the efforts to change the demographic structure of Kirkuk," Turkish Prime Minister Recep Tayyip Erdogan said last month, according to the Cihan News Agency.
Turkish officials recently hosted a conference in Ankara, the Turkish capital, on the future of Kirkuk. Participants included Sunni Arab and Turkmen parties as well as the political party affiliated with radical Shiite cleric Muqtada Sadr, all of whom oppose Kirkuk's inclusion in Kurdistan. None of the main Kurdish parties were invited, and Kurdish lawmakers responded angrily, denouncing what they described as Turkish interference.
Against this backdrop of ethnic, political and regional tensions, Iraq's new constitution mandates that a referendum on control of Kirkuk be held by the end of this year. If the vote goes ahead as scheduled, most analysts expect the Kurds to win.
Kurdish bureaucrats are pushing through little-noticed administrative decisions that will take away the voting rights of tens of thousands of Arabs.
Last year, at least 325 people were killed and 1,390 wounded in this city of about 1 million. During the first three weeks of this year, bombings and assassinations left 23 dead and 102 injured, police say. And on Sunday, police say, two car bombs killed 11 people and wounded 34.
"We expect increased violence when we get closer to" the referendum, said Maj. Gen. Anwar Mohammed Amin, the top Iraqi commander in Kirkuk.
The emergence of fighters from two radical Islamic groups with ties to Al Qaeda after years of lying low is especially troublesome, officials say. The groups, known as Ansar al Sunna and the Islamic Army in Iraq, have launched a bombing campaign targeting politicians and civilians. Their aim is to foment violence between ethnic and sectarian groups much as they have done in Baghdad and elsewhere, officials say.
Painting Iraq's Sunni Arab guerrillas as Al Qaeda associates serves Kurds in their goal of taking control of Kirkuk and its environs by making the aims of their rivals seem less legitimate.
Assassinations, bombings and attacks on Kurdish parties' headquarters by Shiite militias and Sunni groups linked to Al Qaeda "are now all part of Kirkuk's violent landscape," said a report last month from the Washington Institute for Near East Policy.
Turkmen and Arab politicians also have been targeted in apparent retaliation by Kurds.
"Kirkuk is as likely as Baghdad to produce a calamity that can fracture Iraq," the report's authors wrote, recommending a delay of the referendum. The International Crisis Group, a nonprofit think tank based in Belgium, and the U.S. government's bipartisan Iraq Study Group also have recommended postponement.
But for Kurds, this year presents a historic opportunity they won't part with willingly.