A young Russian blogger helping to organise a major rally against Vladimir Putin's 12-year rule accused Friday the security forces of putting pressure on his parents over his political activities.
Ilya Klishin, a 24-year-old blogger and one of the organisers of the next anti-Putin protest on February 4, said the FSB security service contacted his mother in the central Russian city of Tambov where she lives.
The interior ministry's anti-extremism department questioned his father earlier Friday, Klishin added.
"They are trying to put pressure on me by intimidating my parents," he told AFP after writing about the incidents in a message on Facebook.
"It is apparently linked with the fact that I was and am involved in organising the rallies in support of honest elections through social networks."
Klishin said officials grilled his father about his son's visit to the Volga city of Kazan in the Tatarstan region earlier this month and said they were looking into his possible involvement in inciting ethnic discord.
"The matter is taking a completely Kafkaesque turn," Klishin said on his Facebook page.
"I went there to see the ancient city," Klishin said. "Local organisers of protests in support of fair elections did want to meet me in Kazan but we never met."
Russia's Western-funded observer group Golos, which exposed mass violations before and during a fraud-tainted parliamentary election last month, has said the FSB security service also put pressure on its regional employees, although Moscow-based staff were not openly targeted.
Two opposition activists, ex-member of parliament Vladimir Ryzhkov and Gennady Gudkov, a member of populist A Just Russia, earlier this week also accused the security services of harassment after a video recording of their private conversation surfaced on the Internet.
Gudkov said the professional quality of the recording pointed to the involvement of the special services, saying the FSB, a successor to the feared KGB, used Soviet-style methods to intimidate Kremlin opponents.
Putin is wrestling with the worst legitimacy crisis since coming to power but his advisors say he remains Russia's most popular politician despite the recent outburst of protest against his rule.
Currently Russia's prime minister, Putin is seeking to return to the presidency in March elections.
Tens of thousands of people took to the streets during two previous large opposition rallies last month.