The semi-official ISNA news agency on Thursday quotes Intelligence Minister Mahmoud Alavi as saying the matter is under investigation and it is "too soon to say" if Saudi Arabia was involved.
Saudi and Iranian leaders accuse each other of sponsoring militant groups. He concludes by threatening the royal family of Saudi Arabia and promises, "after Iran, it will be your turn". But no proof or specifics were offered. In 2014, the Democratic Party of Kurdistan Iran, an opposition party, published a report about increasing Islamic State activities in Iranian Kurdistan that singled out Sadeghi as a prominent recruiter who, at times, held sessions in a local mosque. Because they haven't buckled under aggression from Saudi Arabia and threats from Israel? The Saudis point to Iranian support for Hezbollah and Hamas, while Iran says Saudi preachers and financial support aided the rise of al-Qaeda and Islamic State.
Egypt's Foreign Ministry offered its condolences to the families of the deceased on Thursday and called on the worldwide community to intensify its efforts to fight terrorism and its sources of funding.
Sunni-majority Saudi Arabia and Shiite Iran have had strained relations throughout their history and have been involved in a sectarian feud for more than 1,000 years.
Islamic State claimed responsibility for the suicide bombings and gun attacks on parliament and the mausoleum of the Islamic Republic's founder, Ayatollah Ruhollah Khomeini, that killed 17 people on Wednesday.
Iran's official IRNA news agency is reporting that police have killed four Islamic State group-linked gunmen in the country's south. He did not elaborate.
With the latest arrests, the number of people detained since June 7 in relation to the attacks in the capital or extremist cells has passed 50. Over 40 people were wounded in the attack.
Iranian lawmakers said the intelligence minister had assured them that "all Islamic state elements have been eliminated" in the country.
The authorities have released the name of five gunmen, Iranian citizens who were said to have fought in Mosul and Raqqa.
The ministry also published pictures of their corpses. The Syrian president spoke to his Iranian counterpart Hassan Rohani by phone on Thursday. The attacks were the first claimed by Islamic State inside tightly controlled Iran, one of the powers leading the fight against the militants in Iraq and Syria.
Iran blamed the Wednesday attacks on Saudi Arabia, casting them in the context of a broader regional conflict that encompasses the war inside Syria. Why exactly is Iran a "state sponsor of terrorism"? State TV broadcast the ceremony live.
Mohammad Javad Zarif in a tweet on Thursday called the comments on the attack in Tehran a day earlier "repugnant" and accused the USA of supporting terror. The fact that the attackers are in all likelihood Iranian Kurds, Sunnis from inside the country, is a source of concern, one analyst said.
Washington named Iran as the target of the agreement, worth USD-110-billion, which was signed during US President Donald Trump's visit to the Saudi capital last month.
Trump said the U.S. would "grieve and pray" for the victims, but added: "We underscore that states that sponsor terrorism risk falling victim to the evil they promote".
The Vatican on Friday sent a message of condolence for the victims of the attack.
Strains between Iran and the USA have deepened since Trump took office in January, slapping new sanctions on the Islamic Republic over its ballistic missile program and ratcheting up the rhetoric against it.