A suicide attack on a mosque in south—eastern Iran killed at least 27 people and injured 167, the local governor said on Friday.

Two bombings took place late Thursday at the grand mosque in Zahedan, the capital of Sistan—Beluchistan province. The bombs went off within minutes of each other at the mosque’s gate.

Governor Ali—Mohammad Azad told state television that because many of the injured were in critical condition, the death toll could increase.

The radical Sunni group Jundollah, meaning Soldiers of God, claimed responsibility for the bombing as retaliation for the execution last month of its leader Abdolmalik Rigi.

Among those killed were members of the Islamic Revolutionary Guard Corps stationed nearby.

An official of the Revolutionary Guards blamed the United States and Israel for the bombing.

Given their support for the Jundollah group, “There should be no doubt that these countries are also behind the latest bombings,” General Yadollah Javani was quoted as saying by Fars news agency.

U.S. Secretary of State Hillary Rodham Clinton condemned the attacks and called for the perpetrators to be held accountable.

The U.S. has constantly denied Iranian charges of supporting Jundollah, but Tehran said Rigi confessed before his execution to having had direct links with the U.S.

Sistan—Beluchistan province borders Afghanistan and Pakistan and is a major drug—trafficking region as well as one of the country’s most unstable areas.

Iran accused Rigi and his group of trafficking illegal drugs, kidnapping and bombings in Sistan—Baluchistan and sowing discord between the Shiite majority and the Sunni minority across Iran.

The group claimed responsibility for a bombing in the province in October that killed more than 40 people, including 15 senior members of the Revolutionary Guards.