TIKRIT, Iraq, July 8 (Xinhua) -- The death toll from a suicide bombing attack at a Shiite shrine in Iraq's central province of Salahudin early on Friday rose to 35 and more than 70 others were wounded, a provincial security source said.
The attack began shortly after midnight when three suicide bombers wearing explosive belts and disguised in military uniforms crossed security checkpoints and entered near the mausoleum of Saiyd Mohammed in the town of Balad, some 80 km north of the Iraqi capital of Baghdad, the source told Xinhua on condition of anonymity.
One gunmen detonated his explosives belt at the marketplace outside the shrine and another at one of its gates, the source said, adding that two mortar rounds landed at the scene at the time of the blasts.
The third suicide bomber threw two hand grenades at a crowd of Shiite pilgrims before he blew up himself among them, the source added.
"A total of 35 people were killed and some 70 others wounded, some of them were in critical condition," the source said, citing a medical source from the nearby hospital in Balad.
Earlier in the day, a security source told Xinhua that at least 20 people were killed and some 70 others wounded when two suicide bombers detonated themselves at the shrine, while other gunmen took many Shiite pilgrims hostages.
He said the gunmen, who believed to be members of Islamic State (IS) group, also held an unknown number of Shiite pilgrims hostages inside the shrine, but the provincial security source denied that they took hostages, saying some people were caught inside the shrine.
The battle with IS caused damages to the shrine and set fire to some surrounding buildings, the source added.
In the morning, the IS militant group claimed in an online statement the responsibility for the attack, saying that three suicide bombers, including a female, attacked the shrine and killed dozens of Shiite people. The statement could not be independently verified.
The revered Imam is the son of Imam Ali al-Hadi and the brother of Hasan al-Askari, the 10th and 11th of the 12 most revered Shiite Imams respectively. The Imam died in the 9th century and his tomb lies in the domed shrine constructed in Balad.
Iraq is currently witnessing a wave of violence since the IS terrorist group took control of parts of Iraq's northern and western regions in June 2014.
An IS militant conducted a suicide bombing attack in Iraq's capital of Baghdad on Sunday which killed 292, the health ministry said early Thursday.
"The government has handed over 115 bodies to their families and identities of 177 people have yet to be determined," Health Minister Adila Hammoud said in a statement.
A suicide bomber detonated a car loaded with explosives in front of a shopping center in the commercial district in southern Baghdad on Sunday, which is the deadliest bombing attack since the U.S. invasion in 2003.
The Islamic State group claimed responsibility for the attack that also left another 200