Russian authorities on Thursday froze hundreds of bank accounts linked to embattled opposition leader Alexi Navalny in what his supporters say was a trumped-up effort to crack down on his political movement ahead of planned nationwide demonstrations this weekend, according to a report.

Investigators said bank accounts belonging to Navalny’s anti-corruption foundation, his campaign headquarters, and more than 100 linked individuals and legal entities were frozen as part of an investigation into alleged money laundering.

Thursday’s crackdown follows a major opposition rally on July 27 in which demonstrators protested a decision to exclude a dozen independent candidates from the ballot for next month’s local election in Moscow. The protests ended with nearly 1,400 arrests.

Navalny, who had been serving a 30-day sentence for calling an unsanctioned protest, was rushed to the hospital the next day from a detention facility with a severe allergy attack that his longtime physician said was consistent with chemical poisoning.

ROCKET ENGINE EXPLOSION AT RUSSIAN MILITARY BASE KILLS 2, INJURES 4, OFFICIALS SAY

Authorities on Thursday searched the Moscow office of Navalny’s foundation and the homes of several of his allies, taking away computers and documents as part of a supposed money-laundering investigation, Reuters reported. Navalny and his supporters maintain his anti-corruption foundation is transparent about its donations.

CLICK HERE TO GET THE FOX NEWS APP

Navalny’s allies were planning follow-up demonstrations across the country on this Saturday.

The Associated Press contributed to this report.