brian nicol , 32 from glasgow , scotland , died while staying in a villa .
his desperate friends dragged mr nicol , who was born in glasgow , out of the water and tried to save him .
the group had been on a night out in marbella after jetting to have drowned , it 's too early at this stage to say why it happened .
sources close to the investigation said they had been told the group had gone out for the evening before returning to the villa to carry .