French firefighters secure the street as police conduct an investigation after two Frenchmen were arrested in Marseille, France, April 18, 2017 for planning to carry out an "imminent and violent attack" ahead of the first round of the presidential election on Sunday, France's interior minister said. REUTERS/Philippe Laurenson

BRUSSELS (Reuters) - A man held in France over a foiled plot to stage an attack ahead of the first round of France’s presidential election was also sought by Belgian authorities, Belgium’s federal prosecutor said.

Clement Baur, 23, was one of two people detained on Sunday in Marseille and authorities said he had plotted an “imminent and violent attack”.

“Clement B. was wanted for questioning. However, there has been no trace of him in Belgium since the end of 2015,” Belgium’s federal prosecutor said on Wednesday.

The prosecutor added Belgium had cooperated with French authorities to find Baur, without giving further details. It also did not say why he was wanted in Belgium.