Romanian police raided houses on Saturday linked to a probe into alleged irregularities in the first-round presidential election win of far-right outsider Calin Georgescu, a day after the top court cancelled the imminent run-off.
The annulment comes after a spate of intelligence documents declassified this week by the presidency detailed allegations against Georgescu and Russia, including "massive" social media promotion and cyberattacks.
The court's move sent shockwaves across the EU and NATO member state bordering Ukraine and opened the way for a new electoral process to start from scratch while a new government is due to set a date for a fresh vote.
Three houses in Brasov city in central Romania were being searched on Saturday as part of the investigation "in connection with crimes of voter corruption, money laundering, computer forgery," said a statement from the prosecutor's office.
It said the swoop targeted a person involved in the "illegal financing of the electoral campaign of a candidate for the presidency of Romania, through the use of sums of money," without naming Georgescu.
The prosecutor's office would not name the person at the heart of the operation either.
The investigations also concern the violation of the law on the prohibition of organisations and symbols of a fascist, racist or xenophobic nature, the statement added.
Little known outsider Georgescu, who unexpectedly topped the first round of voting on November 24, was favourite to win the second round on Sunday against centrist pro-EU contender Elena Lasconi, several polls revealed.
But the documents drawn up for a top security council meeting after the first round of voting "revealed an aggressive promotional campaign, in violation of electoral legislation, and an exploitation of algorithms to increase the popularity of Calin Georgescu at an accelerated pace".
One user paid $381,000 to those involved in the promotion of Georgescu between October 24 and November 24, according to one of the documents.
Based on those claims, the constitutional court on Friday unanimously decided to annul the entire electoral process to ensure its "correctness and legality".
The United States said it had faith in Romania's institutions and called for a "peaceful democratic process".
Georgescu, the 62-year-old former civil servant, has fervently campaigned for an end to aid for neighbouring Ukraine on social media platforms especially on TikTok, a position that sparked concerns over the future direction of the reliable NATO ally.
The EU and NATO sceptic blasted the court ruling as "a formalised coup d'etat" and said democracy was "under attack".
Romania's pro-EU President Klaus Iohannis said he would stay in his post until a new government that emerges from legislative elections last weekend can be formed to set a new presidential election date.
Romania is a "target for aggressive Russian hybrid actions, including cyberattacks and hacks and leaks and sabotage", the declassified documents said.
More than 85,000 cyberattacks were identified, according to Romanian authorities.
