LONDON — Three Iranian spies conducted surveillance of journalists at a Persian news channel critical of the theocratic government in Tehran and the group plotted to violently harm at least one of their targets, a British prosecutor said Tuesday.

Mostafa Sepahvand, 41, Farhad Javadi Manesh, 46, and Shapoor Qalehali Khani Noori, 57, went on trial in Woolwich Crown Court on charges of engaging in conduct likely to assist Iran’s foreign intelligence service between August 2024 and March 2025.

Prosecutor Bill Emlyn Jones said people criticize Iran “at their peril” and that Iran International, a London-based satellite channel, had “come under particular attack” for its opposition to Tehran. He reminded jurors that former leader Ayatollah Khomeini ordered the death of Salman Rushdie in 1989 for his novel “The Satanic Verses,” and noted the vicious 2022 stabbing of the author in New York.

“In this trial, we are concerned with steps being taken, here in London, on behalf of the Iranian regime, to target journalists and others considered to be hostile to, or even just critical of, the Iranian regime,” Emlyn Jones told jurors.

“Their ultimate objective was that one or perhaps more than one of these targets would be subjected to serious violence — no doubt as retribution for their criticism of the Iranian regime and to try to silence and deter others who might dare to voice such criticism.”

The group spied on journalists Mojtaba Pourmohsen and Kambiz Hosseini, both journalists for Iran International, as well as Jonathan Turner, a founding member of U.K. Lawyers for Israel, Emlyn Jones said.

Messages between the group showed that they knew the color and make of Hosseini’s car and the name of his dog.

“You can imagine the fear and psychological impact caused to him by discovering that all of those details about him, including the name of his dog, were known to the Iranian intelligence services,” Emlyn Jones said.

Messages read in court showed Sepahvand telling an associate he would “finish off” a target for 150,000 pounds ($199,000). Manesh and Noori allegedly helped to plan an attack.

Sepahvand claims he conducted the surveillance against his will for Iran but only after being threatened and deliberately did a bad job, the prosecution said. Emlyn Jones dismissed the claim as “entirely bogus.”

Manesh and Noori have said they didn’t know they were working on behalf of the Iranian intelligence service.

The three have pleaded not guilty to all charges.