Aftermath of the bombings
At least 35 people have been killed and more than 50 injured in a double suicide bombing north of the Iraqi capital, Baghdad, army sources say.
The two attackers mingled with a crowd of would-be recruits at an army base in the city of Baquba and then blew themselves up simultaneously, they say.
At least one of the bombers is said to have been disguised as a soldier.
Meanwhile, US forces in Iraq say they have detained 15 suspected insurgents, including an alleged al-Qaeda leader.
The bomb attacks at the al-Saad army camp in the east of Baquba took place at about 0800 (0500 GMT).
Baquba, 60km (35 miles) from Baghdad, is the capital of Diyala province - one of the most dangerous parts of Iraq.
Although violence in Iraq is at its lowest level since 2004, frequent attacks continue throughout the country.
Iraqi army sources said the bombers - one dressed in an Iraqi military uniform, the other in civilian clothing - mingled with the crowds of young recruits before blowing themselves up.
"We were about 30 people standing at the entrance," 17-year-old Falah Ali Hussein, who was injured in the blasts, was quoted as saying by the AFP news agency.
"They had just called our names when suddenly there was a big explosion."
US military spokesman Maj Gen Mark Hertling told the BBC that Diyala remained a centre of insurgent activity despite US operations.
"We have been very forceful in pursuing al-Qaeda and other insurgents out of the major cities in Diyala," he said.
"They, the enemy, are trying to re-assert themselves into the major cities... But we've pursued al-Qaeda and other terrorists into the more rural areas."
Gen Hertling said that the suicide bombing cell responsible for the attack had been one of two that security forces were watching closely.
"We knew that they were about to strike but it's very difficult as you can understand to prevent something like this from happening."
Thousands of army recruits have been killed by insurgents in similar attacks across Iraq in recent years.
Despite this, many young men are still willing to join the army - one of the few sources of employment in Iraq, correspondents say.
Iraqi army recruits are frequently the target of insurgent attacks
Tuesday's attack was the deadliest since 1 May, when twin suicide bombers killed at least 35 people in the nearby town of Balad Ruz.
Al-Qaeda fighters have sought to regroup in the region after being pushed by the Iraqi and US forces from former strongholds further south.
Iraqi military officials have recently said they plan to launch an offensive in the region to rein in remaining militants.
Suspected insurgents held
In another development, US forces in Iraq said they had detained 15 suspected insurgents, including an alleged leader of al-Qaeda in Iraq, whom they did not name.
They say six of the insurgents were captured in Baghdad, and that one of them had co-ordinated bomb attacks in the southern belt around the city.
The US military says other insurgents were captured in Iskandariyah, south of the capital, Hawijah near Kirkuk, Balad, north of Baghdad and Mosul.