A VTS operator receives a MAYDAY RELAY from a vessel that has overheard a distress call. The VTS has not heard the original distress call directly. What is the operator's first action according to standard procedure?

1. Acknowledge receipt of the MAYDAY relay and immediately inform the appropriate Rescue Coordination Centre (RCC).
2. Immediately assume control as the on-scene coordinator for the SAR incident.
3. Instruct the relaying vessel to proceed to the distress position and report back.
4. Acknowledge the MAYDAY relay and then re-broadcast it on all available channels.