Russia's main opposition leader Alexei Navalny said Tuesday that authorities had frozen all of his bank accounts and those of his family, including his elderly parents.

"All accounts have been blocked," Navalny, an anti-corruption campaigner who has emerged as President Vladimir Putin's most prominent critic, said on Twitter.

His spokeswoman Kira Yarmysh told AFP that the accounts had been frozen due to a money-laundering probe against Navalny's Anti-Corruption Foundation.

Navalny said that because of the blocked accounts his daughter, who is a student at Stanford University, was without money and that his retired parents could not receive their pensions.

"This is quite unpleasant, I won't deny it. My parents are elderly people, pensioners," he wrote in a blog post.

"My child is studying at the other end of the planet by herself -- she's been left without a single cent."

He added that his son no longer had access to his savings account.

Investigators last summer launched a money-laundering probe into Navalny's foundation, which seeks donations from the public, accusing it of taking money that was procured illegally.

In August, a Moscow district court froze 75 million rubles ($1.1 million) held in accounts by the foundation and staff members.

Navalny said his personal accounts had until now remained untouched.

Ivan Zhdanov, the director of Navalny's foundation, said authorities had also blocked the bank accounts of his family.

Investigators have repeatedly accused Navalny's foundation of financial crimes, including money laundering and accepting illegal donations, and frozen its accounts.

Navalny organized some of the biggest protests against Putin in recent years.

In the run-up to local elections in September, Navalny and his supporters organized a wave of protests after popular opposition politicians were barred from standing in the Moscow municipal election, prompting a police crackdown.