The incident has resulted in St Mary’s Way being closed and buildings being evacuated as emergency services respond to the incident.
Here are photos of emergency services at the scene as the event unfolds.
5. Building traffic
Traffic builds near Wearmouth Bridge as surrounding roads remain close Photo: National World
6. On Duty
Northumbria Police officer on duty as emergency services respond to Sunderland city centre incident Photo: National Wold
7. Emergency responders
Emergency responders at the scene in Keel Square Photo: National World
8. Taking action
Officers and officials discuss the plan of action in Keel Square Photo: National World
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