Iran's Revolutionary Guards are blaming Saudi Arabia for a pair of terror attacks Wednesday at symbolic locations in Tehran.
"This terrorist attack happened only a week after the meeting between the U.S. president and the [Saudi] backward leaders who support terrorists. The fact that Islamic State has claimed responsibility proves that they were involved in the brutal attack,” the statement read.
Tehran police chief Hossein Sajedinia was quoted in Iranian media as saying five suspects had been arrested in connection with the attacks that left at least 12 people dead and 42 others wounded at Iran's parliament and a shrine to late leader Ayatollah Ruhollah Khomeini.
IS militants immediately claimed responsibility. It marks the first time the Sunni Muslim group admitted it attacked the majority Shi'ite Muslim country.
U.S. President Donald Trump released a statement reacting to the attacks on Wednesday. He said the U.S. grieves and prays for "the innocent victims" of the attacks, and "the Iranian people, who are going through such challenging times."
He also warned that "states that sponsor terrorism risk falling victim to the evil they promote."
The State Department said the "depravity of terrorism" has no place in the world. Spokeswoman Heather Nauert said the U.S. sends its thoughts and prayers to the Iranian people following the attacks.
The United Nations Security Council said the attacks were "barbaric and cowardly," and stressed that it condemned the attacks "in the strongest terms."
The Security Council reaffirmed that terrorism "in all its forms and manifestations" constitutes one of the most serious threats to international peace and security. It said any acts of terrorism are "criminal and unjustifiable," and called for the perpetrators, organizers, financiers and sponsors of those acts to be brought to justice.
Six of the attackers were killed by Iranian security forces.
The attacks began before noon when several men, dressed as women, stormed the parliament building and killed a security guard. One attacker blew himself up inside the building, and three gunmen were reported killed by police after they took several hostages.
Ali Larijani, the speaker of parliament, called the attack a "minor incident" perpetrated by "some cowardly terrorists." He said "serious measures" would be taken against those responsible.
The shrine attack began about 30 minutes after the parliament attack, and involved three gunmen and a suicide bomber who stormed the site, killing at least one person and wounding several others, according to Iranian media. The reports said police arrested at least one of the attackers and killed another.
The United States condemned the terrorist attacks, with State Department spokeswoman Heather Nauert issuing a statement that said, "We express our condolences to the victims and their families, and send our thoughts and prayers to the people of Iran. The depravity of terrorism has no place in a peaceful, civilized world."
The Islamic State extremist group is at war with Iranian-backed groups in Syria and Iran and views Iran's Shi'ite majority as apostates deserving of death.