WASHINGTON (AP) — The United States on Thursday announced sanctions against a group of Iranian and Turkish people and firms accused of plotting to assassinate former U.S. government officials, dual U.S. and Iranian nationals, and dissidents.

Three Iran- and Turkey-based people; a company affiliated with Iran’s Islamic Revolutionary Guard Corps Quds Force, which is a branch of the country's military; and two senior officials of Iran's Intelligence Organization are accused of being involved in plotting to kill journalists and activists, according to the U.S. Treasury Department.

The sanctions against them block all access to their U.S. money and property and prohibit Americans and American firms from working with them.

The U.S. remains focused on disrupting plots by the Iranian military, which has "engaged in numerous assassination attempts and other acts of violence and intimidation against those they deem enemies of the Iranian regime,” Treasury’s under secretary for terrorism and financial intelligence, Brian E. Nelson, said in a statement.

Several alleged assassination plots have been uncovered in recent years.

An Iranian operative, Shahram Poursafi, was charged last year in a plot to kill former U.S. national security adviser John Bolton in presumed retaliation for a U.S. airstrike that killed Iran's most powerful general, Qassem Soleimani. Poursafi was accused by the Justice Department of offering $300,000 to “eliminate” the Trump administration official. Poursafi, who was identified by U.S. officials as a member of Iran’s paramilitary Revolutionary Guard, is wanted by the FBI on charges related to the murder-for-hire plot.

Prosecutors say the scheme unfolded more than a year after Soleimani, the head of the Revolutionary Guard’s elite Quds Force and an architect of Tehran’s proxy wars in the Middle East, was killed in a targeted airstrike as he traveled from Baghdad’s international airport in January 2020. After the strike, Bolton, who by then had left his White House post, tweeted, “Hope this is the first step to regime change in Tehran.”

Additionally, last October, the Treasury’s Office of Foreign Assets Control sanctioned the 15 Khordad Foundation, which issued a multimillion-dollar bounty for the killing of British-American author Salman Rushdie, who was violently attacked last August at a literary event. Rushdie wrote “The Satanic Verses,” which some Muslims consider blasphemous.

American officials say as recently as 2012, the 15 Khordad Foundation raised its bounty to $3.3 million, claiming the full sum would be given to anyone who killed Rushdie.

Tensions between the U.S. and Iran are high amid months of anti-government protests in Iran and Western anger at Iran’s export of attack drones to Russian forces fighting in Ukraine.