Iran says it has arrested 22 people in connection with a deadly attack on a military parade in the southern city of Ahvaz last Saturday that Tehran blamed on the United States and its regional allies, the Intelligence Ministry was quoted as saying on Monday.
"Some 22 people involved in the attack in Ahvaz have been identified and arrested ... weapons, exclusive material and communication equipment were seized in the house that belonged to the five-member terrorist group that carried out the attack," a ministry statement said, according to the semi-official Tasnim news agency.
Gunmen fired on a viewing stand where Iranian officials had gathered on Saturday to watch an annual parade marking the start of Iran's 1980-88 war with Iraq. Twelve members of Iran's elite Islamic Revolutionary Guard Corps were among the 25 dead.
An ethnic Arab group and the Islamic State group have both claimed responsibility, although neither has presented any conclusive proof.
But Iran says that those responsible for the attack and the detained individuals belong to a separatist group supported "by reactionary Arab states" and are "Takfiris", which is a term for extremist Sunni groups.