Iranian authorities have also arrested seven people it suspects of helping militants involved in attacks, a judiciary official said on Saturday.
A police officer stands guard as vehicles drive in front of Iran's parliament building in Tehran, Iran, Thursday, May 8, 2017.
Iran said earlier Thursday that the five Iranians who carried out the killings had spent time in IS strongholds in Iraq and Syria.
Iranian Police Chief Hossein Ashtari on Saturday also mentioned they had arrested around 60 suspects near Tehran, accused of having links to the deadly shootings and bombing.
Trump and the Saudi king last month signed eight different agreements approving nearly US$110 billion in arms sales to Saudi Arabia.More news: Apple likely to expand NFC capabilities beyond Apple Pay with iOS 11
Meanwhile, another attack took place at the Imam Khomeini Shrine.
It suggested that there were only five attackers rather than the six originally reported. The sources from state security have pointed to Iranian Kurds affiliated with Islamic State the likely perpetrators.
Alavi maintained that 42, 43 terrorists were identified and arrested following the June 7 terrorist attacks, saying some of them were in connection with the Tehran twin attacks and some of them were planning for terrorist acts in the future. All in all, the two events left at least 17 dead and more than 43 injured.
Iran blamed the Wednesday attacks on Saudi Arabia, casting them in the context of a broader regional conflict that encompasses the war inside Syria.
Thousands packed Tehran's streets on Friday to mourn the victims of two suicide bomb and gun attacks, and joined their supreme leader in accusing regional rival Saudi Arabia of involvement in the assaults. "We underscore that states that sponsor terrorism risk falling victim to the evil they promote". Instead, he said that the terrorist attacks would not "influence the will of the nation".
When Daesh (ISIS) called on members of Iran's Sunni minority in March to wage a religious war on their Shiite rulers, few people took the threat seriously.