BUDAPEST (Reuters) - Hungarian authorities said on Friday they had launched an investigation into opposition figure Peter Magyar on suspicions over foreign funding for his campaigns, which have been highly critical of Viktor Orban's government.
There was no immediate comment from Magyar, a 43-year-old lawyer formerly close to the administration who launched a movement in February that has accused the government of corruption and triggered mass marches against Orban.
The investigation into Magyar was announced by the head of the new Sovereignty Protection Office, a body the government set up in December to watch out for signs of what it called foreign interference in Hungarian politics.
Rights activists, U.S. and European officials have criticised the office and the law that established it, saying both could be used to stifle dissent. Any candidate found guilty of getting banned foreign funding can be jailed for up to three years.
"Based on the suspicion of foreign funding attempts, the Sovereignty Protection Office has started an investigation," the head of the office, Tamas Lanczi, told pro-government newspaper Magyar Nemzet.
Lanczi said the investigation was launched after a report by Magyar Nemzet that said Magyar's party was linked to companies connected to former socialist prime minister Gordon Bajnai, who now lives outside Hungary.
Magyar dismissed that report in a Facebook (NASDAQ:META) post on Thursday and said he had not been in touch with Bajnai.
Magyar launched his movement by publicly accusing the government of widespread corruption and running a centralized propaganda machine. Orban aides have rejected his accusations.
In late March, he published a recording of a conversation with Judit Varga, then his wife and Hungary's justice minister, in which she detailed an attempt by Orban aides to meddle in a graft case.
The recording, which is being investigated by prosecutors, has led to large protests and has cast a shadow over Orban's government which had already been reeling from a sex abuse scandal that led to the resignation of the president.
Magyar, who took over an inactive party called Tisza (Tisztelet és Szabadság - Respect and Freedom), is touring the countryside to try to drum up support for his election campaign.
Magyar's party is running in the European elections in June, the first test for the former government insider's ability to challenge the nationalist leader.
Opinion polls suggest that Magyar would get about 13% of the vote, while support for the ruling Fidesz party is mostly unchanged above 45%.