• conduct an internal investigation – проводить служебное расследование
• launch an internal investigation – инициировать служебное расследование
См. также: international ship and port security, into custody, intrusion, introduce a curfew
The bank conducted its own internal investigation into the robbery. (Cambridge English Dictionary)
"Can I ask whether you have initiated any internal investigation into the leaking of my banking status and current account balances?" (The Journal)
