A boy who spent six hours in the sea with two men after their boat capsized off the Queensland coast is fighting for life after the trio’s harrowing ordeal to survive after their boat went to the bottom.

Water police raced to find the trio after receiving a distress call from the 5.2 metre vessel which was taking on water just after 1.30am on Sunday.

A second distress call followed, but then all radio contact ended as sea and air rescuers sped to the vessel’s last known location about 14km off the coast of Caloundra.

The coast guard was immediately deployed and all vessels in the area were notified the boat was sinking, police said.

The trio were spotted in the water by an anchored off-shore tanker which notified authorities and led to their rescue just before 8am.

The seven-year-old boy has been airlifted to Sunshine Coast University Hospital in a critical condition, while the two men – aged 48 and 39 – were brought back to land by marine rescue.

It is understood the men have hypothermia and are being assessed by paramedics.

-with AAP