LISBON, Portugal (AP) — The Lisbon stock exchange suspended trading in Portugal’s national energy provider EDP and its international renewable energy division Monday after media reports said a magistrate had suspended the chief executives of both companies amid a major corruption investigation.

The stock exchange said in a statement that trading was suspended pending the receipt of relevant market information. EDP’s website made no mention of the news reports, and company officials could not immediately be reached.

EDP is one of Portugal’s biggest companies, with significant interests in the U.S. renewable energy market and businesses in 19 countries on four continents. Its biggest shareholder is China Three Gorges, with about 21.5%, whose takeover bid last year failed.

Portugal’s public prosecutor has for eight years been investigating whether Energias de Portugal CEO Antonio Mexia and EDP Renováveis chief João Manso Neto corrupted three members of the Portuguese government in order to obtain financial benefits. The pair have denied any wrongdoing.

EDP - Energias de Portugal, S.A. owns 82.6% of its subsidiary EDP Renováveis, S.A., which in turn fully owns subsidiary EDP Renewables North America LLC.