The report says the sister of a BBC reporter was detained and put in Tehran's Evin prison, where the IRGC is thought to exert considerable control.
IRGC officials then contacted the reporter in London using e-mail information obtained from her detained sister.
They told the BBC staffer that if she talked to them, her sister would be released.
No names were mentioned in the "IranGreenVoice" report, which said the BBC reporter consulted with the head of BBC’s Persian service before she agreed to speak over the Internet with IRGC security officers.
The conversation lasted 40 minutes and took place at her home in London, according to the website.
It said “IRGC officials could see her but she could only hear their voices.”
Following the online interrogation, her sister was released.
Not An Isolated Incident
Two sources familiar with the situation have confirmed the report to RFE/RL.
Sadeq Saba, the director of the BBC’s Persian-language television service, told RFE/RL that a relative of a BBC Persian staff member had been detained in Tehran in an attempt by authorities to put pressure on the London-based BBC employee.
He said he could not discuss any more details because of security issues, but indicated that it wasn't an isolated incident.
“In recent months, the Iranian establishment has put a lot of pressure on the families of some of the BBC Persian service staff," he said. "In some cases, they have been interrogated. In other cases, their passports have been confiscated.
"These measures have been going on in Iran for several months. Recently, a member of the family of a BBC Persian employee was detained and through that person they pressured the BBC staff member in London.”
In October, the BBC reported that Iranian police and officials had been harassing BBC staff by arresting, questioning, and intimidating their relatives in Iran.
Peter Horrocks, the director of BBC Global News, said as many as 10 BBC staffers have experienced such treatment.
Saba claimed Iranian officials are trying to get the BBC staffers to quit their jobs, and he called their tactics "hideous."
“[Iranian authorities] probably feel that the BBC’s style of information is not to their benefit, therefore they want to discredit the BBC and frighten members of the BBC Persian service so that they stop working," Saba said. "These methods by Iran -- particularly, pressuring the families -- is not acceptable in the modern world."
He also said the BBC is determined to continue its work and is exploring possible ways to condemn what he called Iran’s “inhumane” actions through the European Union and human rights groups.
Iranian officials have had a tendency to harass the families of their targets, including political activists and prisoners, but this appears to be the first time they used the Internet for that purpose.
Relatives who have publicized the cases of their loved ones have also been targeted.
In December, the mother of a jailed human rights activist was sentenced to 23 months in prison for talking about her son’s case in an interview.
-- Golnaz Esfandiari