Iran said its security forces on Saturday killed the mastermind of the attacks, and arrested seven people suspected of helping the militants.
This week's attacks at Parliament and the mausoleum of the Islamic Republic's founder Ayatollah Ruhollah Khomeini have exposed shortcomings within the Islamic Revolutionary Guard Corps, which was supposed to be protecting these potent symbols of Iran's revolution.
"The enemy of my enemy is my friend" will not be applied here where Iran and USA are concerned, since the USA recently enhanced their bilateral relationship with Saudi Arabia, the main enemy of Iran.
He concluded his message with a threat to Saudi Arabia, saying that it, too, will be targeted. The Interior Ministry in a statement increased the number of wounded to 52, up from 40.
As the 17 victims were buried on Friday, Iran's current Shiite leader, Ayatollah Ali Khamenei, and parliamentary speaker, Ali Larijani, directed blame at the United States and Saudi Arabia - the nation's fiercest regional rival.
The country's Supreme Leader said the attacks will add to the hatred that Iranians harbor toward the US and Saudi Arabia.
Meanwhile, Iran police chief Gen Hossein Ashtari said several people with connections to the attackers were arrested around the capital area.
Police, who said they were holding six suspects as part of their investigation into the attacks, also increased their patrols in the streets and subway stations of Tehran on Thursday.
Two separate attacks shook Tehran on June 7.
IS has long vowed to attack Iran because the country had deployed military advisers and support to both Syria and Iraq in their fights against the extremist group. The information added that in the raids were also confiscated "many documents and weapons" that were in the hands of the individuals to whom the authorities linked them with "Wahhabi cells", referring to the predominant Sunni Islamic conservative doctrine in Saudi Arabia.
The ISIS group that had claimed the Tehran deadly attacks published a video of five gunmen that appear threatening Iranians of a "slaughter" campaign to be waged by the soldiers of the "Islamic State".
Trump said the U.S. would "grieve and pray" for the victims, but he added: "We underscore that states that sponsor terrorism risk falling victim to the evil they promote".