The US Justice Department said on Tuesday it seized 36 Iranian-linked websites, many of them associated with either disinformation activities or violent organizations, taking them offline for violating US sanctions.
Several of the sites were back online within hours with new domain addresses.
"Today, pursuant to court orders, the United States seized 33 websites used by the Iranian Islamic Radio and Television Union (IRTVU) and three websites operated by Kata’ib Hizballah (KH), in violation of US sanctions," the department said in a statement.
Also spelled Kataib Hezbollah, KH is one of the main Iran-aligned Iraqi militia groups and has been designated a Foreign Terrorist Organization by the United States.
The sites seized included Press TV, the Iranian government's main English-language satellite television channel, and Al Alam, its Arabic-language equivalent. Both came back online using Iranian domain addresses Alalam.ir and Presstv.ir.
The Justice Department said the 33 domains used by IRTVU are owned by a United States company and that IRTVU did not obtain a license from Treasury's Office of Foreign Assets Control prior to utilizing the domain names.
KH also did not obtain a license.
Notices appeared earlier on Tuesday on a number of Iran-affiliated websites saying they had been seized by the United States government as part of law enforcement action.
Iranian news agencies said the US government had seized several Iranian media websites and sites belonging to groups affiliated with Iran such as Yemen's Houthi movement.
The notices appeared days after a prominent hardliner and fierce critic of the West, Ebrahim Raisi, was elected as Iran's new president and after envoys for Iran and six world powers, including Washington, adjourned high-stakes talks on reviving their tattered 2015 nuclear accord and returned to capitals for consultations.