Twenty-seven people died as a result of a terrorist attack outside the Zahedan Jame Mosque late Thursday, Iranian Health Minister Marzieh Vahid Dastjerdi was quoted as saying by the Mehr news agency.
Over 270 were injured in the blast. Eleven are in critical condition.
"Doctors performed operations on 170. The rest are receiving outpatient services," Dastjerdi said, adding that a group of surgeons was dispatched to Zahedan.
According to the IRNA news agency, twin explosions were heard outside the mosque late yesterday afternoon, RIA Novosti reported.
The Jundallah (Soldiers of God) Sunni militant group claimed responsibility for the blasts, calling them a response to the execution of their leader Abdolmalek Rigi, who was arrested by Iranian security forces Feb. 23, the Dubai TV channel Al-Arabiya reported.
They said the attacks were carried out by two suicide bombers - Rigi's relatives - and targeted the Islamic Revolutionary Guards Corps stationed near the mosque.
Jundallah has claimed responsibility for many terrorist attacks in Iran. The group has committed mass murders, armed robberies, kidnappings, and bombings, the Iranian government reports.