BAGHDAD - Two car bombs exploded in Baghdad on Sunday, killing at least 14 people, police and medics said, while a standoff between the Iraqi army and al Qaeda-linked militants in Falluja continued.
No group claimed responsibility for the bombings, but Sunni Islamist insurgents have stepped up a violent campaign in the past year, engulfing Iraq in its worst bloodshed in five years.
Sunday's deadliest blast killed nine people outside a bus terminal in the Allawi district of the capital, near the site of a bombing four days ago at the small Muthanna airfield in which 23 army recruits were slain.
A witness who did not give his name said the bus terminal bomb also targeted army recruits who were registering their names at the airfield. "When they left the airport and came and gathered here, the bomb went off," he said.
The government has asked for volunteers to join its military struggle against al Qaeda, which has expanded its presence in the Sunni-dominated province of Anbar bordering Syria, where the militants are also fighting.
On Jan. 1, militants seized Falluja and parts of the nearby city of Ramadi, the provincial capital of Anbar, raising the stakes in a confrontation with the Shi'ite-led government.
Prime Minister Nuri al-Maliki has deployed tanks and artillery around Falluja, but is allowing time for negotiations aimed at securing the peaceful eviction of the militants of the al Qaeda-affiliated Islamic State of Iraq and the Levant (ISIL).
Security forces and armed tribesmen retook Ramadi last week.
At least 60 civilians and tribal fighters have been killed and nearly 300 wounded in the past two weeks, according to Anbar health officials. No casualty figures were available for militants or members of the Iraqi armed forces.
Residents of Falluja, 70 km (44 miles) west of Baghdad, said most shops in the city centre were open on Sunday, as people prepared for a holiday to mark the anniversary of the Prophet Mohammad's birthday.
Some families who had fled the city were returning, although many still feared a military offensive. Residents said the town of Khalidiya, which lies between Ramadi and Falluja, had come under army fire from mortars and helicopters.
Officials in Baghdad have blamed Iraq's slide back into violence on the conflict in Syria, which has inflamed sectarian tensions and fuelled instability across the region.
Many in Iraq's once-dominant Sunni minority share ISIL's enmity towards Maliki's government, which they perceive as pursuing narrow Shi'ite interests and in thrall to Iran.
But others are deeply hostile to al Qaeda, including tribal leaders whose Sahwa (Awakening) militias helped U.S. troops rout the militants who controlled much of Anbar at the height of Iraq's insurgency and sectarian conflict in 2006-07.
The departure of U.S. troops two years ago weakened the Sahwa fighters, who complained of a lack of government support even as they came under sustained attacks from al Qaeda.