UPDATE Sunday 8.34am: TWO people were knocked unconscious when the fishing charter boat they were on collided with a whale.
RACQ CQ Rescue was on its way to an EPIRB activation off the coast of Bowen when it was diverted north-east to Gloucester Island to help a fishing charter boat.
An RACQ CQ Rescue crewman said the sudden, enormous impact had caused those on board to be violently "thrown about the boat" and that two people were knocked unconscious with another suffering injuries including suspected fractures.
The charter had six people on board at the time.
The crew decided that it was too dangerous to winch the injured onto the helicopter, so the rescuers escorted the damaged boat back to Abel Point Marina.
The injured, including a man with a deep head laceration, were then transferred to Proserpine Hospital for treatment by paramedics.
RACQ CQ Rescue returned to base at Mackay Airport just after 6pm.
The four people on board the boat which had earlier broken down near Gould Reef, off Bowen, and had activated an unregistered EPIRB had been assisted to safety by Volunteer Marine Rescue
INITIAL: FOUR people on board an A1 fishing charter vessel have been taken to Proserpine Hospital in serious but stable condition tonight.
The injuries were a result of a whale making full impact with the port side of the boat at 3.45pm this afternoon north-east of Gloucester Island.
The impact caused the vessel to spin and "decomissioned" one of the engines.
VMR Whitsundays and a rescue helicopter were tasked on standby but it was deemed "too dangerous" to get anyone off
After impact, the 8-person crew returned to the mainland via the Abell Point Marina boat ramp at 6pm, where paramedics were able to apply medical treatment.
A QAS paramedic on the scene stressed that the four people taken to hospital were in varying states but all were in stable condition.
One is suspected to have suffered spinal injuries.
It is unclear what type of whale hit the vessel and how large it was.
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