A kayaker was reported to have been struck by a motorboat shortly after 3pm on the Cleddau River, off Rudders Boatyard, on the Milford Haven Waterway.
The kayaker suffered non-life-threatening injuries and was passed into the care of the Welsh Ambulance Service.
Dale Coastguard Rescue Team, Dyfed-Powys Police and Milford Haven Port Authority Harbour Patrol also attended.
Paul Atkins, from the MCA's Regulatory Compliance Investigations Team, said:
This was an incident with potentially serious consequences, so it's important to find out what happened.
We're appealing to anyone who saw the collision, has video footage or still images, or has any other relevant information that might help, to please
/Public Release. This material from the originating organization/author(s) might be of the point-in-time nature, and edited for clarity, style and length. Mirage.News does not take institutional positions or sides, and all views, positions, and conclusions expressed herein are solely those of the author(s).View in full here.