At least 29 people were killed and 38 were wounded in Iraq on Sunday, after a suicide bomber blew himself up inside Baghdad’s largest Sunni mosque, The Associated Press reported.

Iraqi security officials were quoted by the news agency as having said one of the dead was parliament lawmaker Khalid al-Fahdawi.

Maj. Gen. Qassim al-Moussawi, a spokesman for Baghdad’s military operations command, confirmed the bombing happened inside the Um al-Qura mosque during prayers in the western Baghdad neighborhood of al-Jamiaah.

“I heard something like a very severe wind storm, with smoke and darkness, and shots by the guards,” an eyewitness who was hit in the hand by shrapnel told AP. “Is al-Qaeda able to carry out their acts against worshippers? How did this breach happen?”

AP noted that the attack was reminiscent of a 2006 attack on Shiite shrine in the city of Samarra that nearly brought the country into a civil war.

No group immediately claimed responsibility for Sunday’s bombing, but suicide attacks are generally carried out by al-Qaeda.

Iraqi Prime Minister Nouri al-Maliki released a statement in which he called on Iraqis to stand strong against terrorists and “pursue them wherever they are.”

“Solidarity and unity, and standing as one line behind the army and the police, are the only way to eliminate this danger, which does not differentiate between the Iraqis and targets all of us,” al-Maliki was quoted as having said.

Meanwhile, al-Moussawi said there is a possibility that the bomber had inside help.

“For sure there must have been someone inside the mosque who helped the bomber,” al-Moussawi told AP. “It must have been someone who is protecting the mosque.”