* Suicide bomber kills 23 recruits, wounds 36 in Baghdad
* Falluja reported quiet after tentative deal with tribes
* More than 11,000 families displaced in Anbar - U.N. (Adds Ramadi suicide bombing, Buhriz sniper attack in paragraphs 8-9)
By Alistair Lyon
BAGHDAD, Jan 9 (Reuters) - A suicide bomber killed 23 Iraqi army recruits and wounded 36 in Baghdad on Thursday, officials said, in an attack on men volunteering to join the government's struggle to crush al Qaeda-linked militants in Anbar province.
Brigadier General Saad Maan, spokesman for the Baghdad Security Operations Centre, said the bomber blew himself up among the recruits at the small Muthanna airfield, used by the army in the capital. Maan put the death toll at 22 but health ministry officials said morgue records showed 23 had died.
No group immediately claimed responsibility for the attack, which occurred a day after Prime Minister Nuri al-Maliki said he would eradicate the "evil" of al Qaeda and its allies.
Fighters from the al Qaeda-affiliated Islamic State of Iraq and the Levant (ISIL), which is also at the forefront of Syria's civil war, last week seized control of Falluja and parts of Ramadi, capital of Iraq's western Anbar province.
The Shi'ite-led government has asked for volunteers to join the military effort against al Qaeda, which has regained strength in Sunni-dominated areas such as Anbar partly by exploiting widespread Sunni resentment over Maliki's policies.
Bloodshed in Iraq has returned to its highest level in five years, with the United Nations reporting 8,868 people killed in 2013 - a surge of violence partly fuelled by the war that began in Syria some months before U.S. forces ended their nine-year occupation of Iraq in 2011.
Also on Thursday, a suicide car bomber attacked a checkpoint in eastern Ramadi, killing three special forces soldiers and wounding four, police and medical sources said.
A sniper killed two more members of the special forces in Buhriz, north of Baghdad, according to security officials.
And a car bomb exploded near a health department building in Tikrit, the hometown of deposed Sunni leader Saddam Hussein. An ambulance driver was killed and five other people wounded.
Residents in Falluja reported a calmer day after some overnight mortar fire. Militants were keeping a low profile. Troops on the outskirts made no attempt to enter the city, many of whose 300,000 residents fled after clashes last week.
But it is not clear whether a deal reached between Maliki's government and Sunni tribal leaders, under which the militants would withdraw and the army would stay outside Falluja, can end the struggle for the city 70 km (45 miles) west of Baghdad.
"We don't want this city to suffer and we will not use force, as long as the tribes announce their readiness to confront al Qaeda and expel it," Maliki said on Wednesday.
The violence has alarmed Western governments and pointed up the links between Sunni militants in Iraq and Syria, but Iraq's oil industry and its foreign investors see no cause for panic, given that main oil fields are far from Anbar.
Thousands of civilians streamed out of Falluja after ISIL and allied Sunni tribesmen overran police stations 10 days ago, but a few have returned in hopes that negotiations will avert a full-scale army assault on a city that endured two devastating U.S. offensives against Sunni insurgents there in 2004.
According to the United Nations, more than 11,000 families have fled their homes in Anbar province. U.N. agencies delivered the first relief supplies to the displaced people on Wednesday.
"It is essential to meet the urgent humanitarian needs of the people in Anbar province, particularly those in Falluja and surrounding areas," Nikolay Mladenov, the U.N. envoy to Iraq, said in a statement on Thursday.
Human Rights Watch said combatants on both sides were causing civilian casualties in Anbar, with Iraqi government forces apparently using indiscriminate mortar fire, while al Qaeda and its local allies were attacking from populated areas.
"A government blockade of Falluja and Ramadi has resulted in limited access to food, water and fuel for the population," the U.S.-based group said in a statement.
The blockade is by no means total. A Reuters reporter left Falluja and returned there on Thursday with no questions asked at a checkpoint where a dozen tanks and other armoured vehicles were parked with their gun barrels pointed at the city.
More shops and bakeries were open in Falluja than the previous day. The price of a jerrycan of kerosene had fallen to 20,000 dinars ($17) from as much as 40,000 on Wednesday.
Small groups of gunmen lurked in some places, but in general their presence was less visible than before, residents said. Burnt-out cars wrecked in fighting still littered the streets, but some traffic police reappeared at intersections.
Nevertheless, civilians remained wary, with some believing that an army assault was still imminent.
"It is a game," said one man who asked not to be named. "Why is the army on the outskirts of the city and why is nobody targeting them? I think they are preparing to raid the city."
In the Kurdish city of Arbil, people who had fled their homes in Falluja said they had feared fierce fighting.
"As soon as we heard the army was going to attack the city we became very worried because civilians will be the sacrifice," said Monzher Hazallah, head of a family of nine.
He said masked gunmen had taken over Falluja, but it was not clear how many were ISIL fighters, suggesting that Maliki had emphasised the role of al Qaeda's role, rather than Iraqi Sunnis with grievances, to justify an attack on the city.
"In our opinion, he chose the timing as part of his election campaign," he said, referring to parliamentary polls in April when Maliki could win a third term.
Abdel Kareem, who fled Falluja five days ago with his family of 10, said army bombardment had killed one of his neighbours: "The army is shelling residential districts," he said. "You don't know where it will come from next."
($1 = 1,164 Iraqi dinars) (Additional reporting by Isabel Coles in Arbil, Kamal Na'ama in Falluja and Suadad al-Salhy and Kareem Raheem in Baghdad; Editing by Alastair Macdonald)