At 1209hr a call was received from a jetski with 2 POB.The jetski was between Thornton and the Rurima Islands with a battery problem and requesting assistance.The sea conditions were very good with 7-10kt wind from the N and a calm sea.A good samaritan heard the call and located the jetski which was taken under tow back to Thornton.Both jetski and boat were safely back at the Thornton wharf at 1309hr.A big thank you to the good samaritan.