PetroVietnam's deputy chief executive and other current and former employees of the state-owned company have been arrested as part of an ongoing investigation into the Ocean Commercial Bank.
On 31 August, deputy chief executive Ninh Van Quynh and some of the group's officers were arrested.
PetroVietnam said it was co-operating fully with the law enforcement agencies, and the arrests had not negatively affected the company's production and investment activities.
