This train will detonate (tentative) is a cutscene in Resident Evil 2. It plays during the Claire B scenario.
Computer: "Warning: biohazardous outbreak imminent. The emergency system has been activated. This train will detonate. Repeat: this train will detonate."
Claire Redfield: "No! What's wrong with this thing?"
Leon Scott Kennedy: "I don't know. The door won't open!"