At least 31 people were killed Tuesday in a double suicide bombing on a Shia mosque in Baghdad.
Sixty people were also wounded in the attack that came amid increasing sectarian strife in the country.
The two suicide bombers in Tuesday's attack shot security guards before entering the mosque and detonating their explosive-laden vests.
The target of the attack was the Shia religious center Habib ibn al-Mudhaher Husseiniyah, in northern Baghdad, located next to Immam al-Sadiq university.
Many of the dead and injured were students taking a break from school to pray.
"What sins did these innocent students commit?" asked student Mustafa Kamil, in an interview with AFP.
"They gathered here for prayer. Does any religion accept killing innocent human beings?"
No one claimed responsibility for the attacks, but bombings against Shias in Iraq are frequently the work of Al Qaeda's Iraq branch.
More from GlobalPost: Iraq: Wave of bombings kill scores, wound hundreds in Baghdad and beyond
Violence in Iraq has spiked in recent months, with May registering as the deadliest month since 2008. Over 1,000 Iraqi civilians and security officials killed were killed last month. There are fears that Iraq will once again descend into sectarian bloodletting.
"The increase in attacks is linked to anti-government protests in predominantly Sunni-Arab provinces, namely Anbar, Ninewa, and Kirkuk," Jared Levy, director of Iraq Operations at Dunia Frontier Consultants, told GlobalPost.
"The insurgent groups that are perpetrating these attacks on Shia targets are hoping to create a backlash, either in the form of a government security forces crackdown on Sunni neighborhoods or provinces, or reciprocal attacks by Shia militias."
"As long as there is lingering political instability and a feeling of broad political marginalization in Sunni communities, Sunni insurgent groups will look to exploit these feelings and foster cyclical violence," he added.
On Monday, at least 12 people died in Iraq after a blast at a roadside restaurant and bus depot. The day before, at least 51 people were killed in a wave of bombings across the country.
More from GlobalPost: Attacks across Iraq kill as many as 73