WASHINGTON, July 16 (Xinhua) -- U.S. President Barack Obama condemned the "outrageous terrorist attacks on a mosque" in Iran, a statement released by the White House said on Friday.
"The murder of innocent civilians in their place of worship is an intolerable offense, and those who carried it out must be held accountable," the statement said.
"Together, the people of the world must condemn and oppose all forms of terrorism, and support the universal right of human beings to live free from fear and senseless violence," it added.
At least 20 people were killed on Thursday in two explosions that hit a mosque in Iran's southeast city of Zahedan, the restive capital of Sistan-Baluchestan province.
In an email sent to pan-Arab TV channel al-Arabiya, the Jundallah rebel group claimed it launched the attacks in retaliation for Iran's execution in June of the group's leader, Abdolmalek Rigi.
On June 20, Iran hanged Abdolmalek Rigi after he was convicted of various charges including armed robbery, bombings in public places, armed attacks on the army, police and civilians, assassination attempts, disrupting regional stability, kidnapping and murder.
The Jundallah group was founded by and had been under the command of Abdolmalek Rigi who claimed to fight for the rights of Sunni Muslims in Iran. Iran said the group was behind numerous acts of terror, including bombing and kidnapping.