Telegram CEO Pavel Durov has been moved to an investigative judge following the conclusion of his four-day interrogation by French police, according to a judicial source on Wednesday.

The investigative judge will now decide whether to formally investigate the Russian-born billionaire, who was arrested as part of an organized crime probe on the messaging app. A decision is anticipated later on Wednesday.

Being under formal investigation in France does not signify guilt or inevitably lead to a trial, but suggests that the judges believe there is sufficient evidence to continue the investigation. These investigations can span several years before culminating in a trial or being discontinued.