Belgian security agents bugged a corporate box at the RSC Anderlecht football stadium that was being used by Chinese tech giant Huawei to schmooze members of the European Parliament.

They also listened into other conversations involving one of Huawei’s leading lobbyists, including in his car. The surveillance operations, confirmed by three people with close knowledge of the investigation, formed part of a wide-ranging probe into allegations of corruption that was first revealed in March. They contributed to the Belgian prosecutor’s decision, reported by POLITICO on Monday, to request that a group of MEPs have their immunities lifted so they can be investigated.