TEHRAN: The attackers who stormed Tehran's parliament complex and the revolutionary leader's shrine on Wednesday were Iranian nationals who had joined the Islamic State group (IS), a top official said.
The six attackers "were Iranian and joined Daesh (IS) from some parts of Iran," said Reza Seifollahi, deputy secretary of Iran's Supreme National Security Council, on state TV late Wednesday.
It was the first attack in Iran claimed by IS, which had threatened to step up its campaign in the country in recent months.
Iran is a key fighting force against IS and other groups in Iraq and Syria, and the Sunni jihadists consider Iran's Shiite Muslims to be apostates.
Shiites make up roughly 90 percent of Iran's population, but the country also has a sizeable Sunni minority, particularly around its restive borders with Iraq and Pakistan.