BERLIN (AP) — German lawmakers on Thursday lifted the immunity from prosecution of one of the far-right Alternative for Germany party’s top candidates in the upcoming European Parliament election as he faces an investigation.

The German parliament’s lower house, or Bundestag, voted to lift Petr Bystron‘s immunity to clear the way for searches in connection with the investigation. Lawmakers from Alternative for Germany, or AfD, abstained.

Prosecutors in Munich said they were investigating a member of the Bundestag on an “initial suspicion” of corruption and money laundering, without offering more details. They would not identify the lawmaker, but German news agency dpa and other media reported that it was Bystron.

Prosecutors said properties in Berlin, Bavaria and on the Spanish island of Mallorca were being searched Thursday and documents and other evidence seized.

Bystron is currently a lawmaker in Germany’s national parliament but is the no. 2 on his party’s list for the June election to the European Union’s legislature. Last month he denied allegations in a Czech daily that he may have received money from a pro-Russian network.

AfD’s co-leaders, Alice Weidel and Tino Chrupalla, said in a joint statement that the lifting of Bystron’s immunity and searches of his home and office space were “a serious event” and that no proof has been offered so far for the accusations against him.

They said AfD’s parliamentary group hopes for a quick conclusion to the investigation so that the impression doesn’t arise of an attempt by authorities to influence the European Parliament election campaign.

The investigation adds to events that have cast an unflattering light on AfD, which has enjoyed strong support in recent months.

Last month, an assistant to Maximilian Krah, a European Parliament lawmaker who is the top candidate on AfD’s list for next month’s election, was arrested on suspicion of spying for China. German government and mainstream opposition lawmakers have assailed the party for its alleged closeness to Russia and China.

On Monday, a court ruled that Germany’s domestic intelligence agency was justified in putting the party under observation for suspected extremism. AfD has portrayed the designation as a political attempt to discredit the party and said it will seek to appeal.

And on Tuesday, another court ruled in a separate case that Björn Höcke, the leader of one of AfD”s regional branches and one of the party’s best-known figures, knowingly used a Nazi slogan in a speech and ordered him to pay a fine.