Iranians inspect the Shohada Hosseiniyeh mosque after an explosion Saturday.
1 of 2 While an initial report said a homemade bomb exploded, a local police commander said it appeared to be a case of negligent handling of live munitions inside the mosque.
The local prosecutor and an Iranian foreign ministry spokesman suggested the possibility of sabotage had not been ruled out.
The blast and fire occurred about 9 p.m. Saturday in the Rahpouyan-e Vessal cultural center section of Shohada Hosseiniyeh mosque in the city of Shiraz, Iran's state-run news agency reported. Watch the congregation react to the blast »
Survivors were being treated at 12 hospitals, the agency reported.
Iran's Fars news agency estimated 800 people, mostly young, were gathered at the mosque Saturday to hear a prominent local cleric's sermon denouncing Baha'i and Wahhabi faiths -- both of which are considered heretical by some Shiites. Watch why most of the victims appear to be men »
Fars' initial reports said a homemade bomb was to blame, but provincial police Commander Ali Moaeyri later said it "was not sabotage."
"Some live munitions may have been left behind at that location, which could have been the cause of the explosion," Moaeyri said.
The police commander said the munitions were apparently left behind after a "Sacred Defense" exhibition was held at the mosque, which also serves as a cultural center. "Sacred Defense" is a local reference to the Iran-Iraq war of the 1980s.
Local militia groups -- known as Basij -- often use the mosques for meeting places.
The police commander's explanation, however, is apparently not the final word.
Shiraz prosecutor Hojatoleslam Jaber Baneshi told Iran's official news agency, the IRNA, that a committee was investigating the cause. He did not rule out sabotage.
Iranian Foreign Ministry spokesman Mohammad Ali Hosseini also said the cause was uncertain.
"We cannot make any prejudgments regarding the bomb blasts, and no group has claimed responsibility," he said.
Bombings are unusual in Iran, though the predominantly Shiite country has endured sporadic attacks in recent years.
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