Iranian Revolutionary Guards launched the mid-range ground-to-ground missiles from western Iran into the Deir al Zour region of eastern Syria, killing a "large number" of terrorists and destroying their equipment and weapons, it said.
The missiles targeted the "headquarters and gathering centers of Takfiri terrorists supporting and building car bombs", it said.
Military leaders and officials in Iran, a predominantly Shi'ite country, often refer to Sunni Muslim radicals as Takfiris.
The attack last week, which included shootings and at least one suicide bombing, was on Iran's parliament and the shrine of Ayatollah Ruhollah Khomeini, the founder of the Islamic Republic.
Senior Iranian officials, however, have pointed a finger at Saudi Arabia, Iran's Sunni regional rival.