WASHINGTON — The United States has sanctioned four Iranian intelligence operatives behind a failed plot to kidnap a US journalist and human rights activist, the US Treasury Department said on Friday.

The sanctions come after US prosecutors in July charged the four with plotting to kidnap the Iranian-American journalist Masih Alinejad.

"The Iranian government's kidnapping plot is another example of its continued attempt to silence critical voices, wherever they may be," said Andrea Gacki, head of Treasury's Office of Foreign Assets Control.

"Targeting dissidents abroad demonstrates that the government's repression extends far beyond Iran's borders."

The sanctions block all property of the four Iranians in the US and prohibit any transactions between them and US citizens. The department added that other non-Americans who conduct certain transactions with the four could also be subjected to US sanctions.

Those sanctioned include senior Iran-based intelligence official Alireza Shahvaroghi Farahani and Iranian intelligence operatives Mahmoud Khazein, Kiya Sadeghi, and Omid Noori, Treasury said. — Agencies