GIBRALTAR Four men were admitted to hospital yesterday morning suffering from burns after a small explosion occurred in their fishing boat as they were refuelling at the Giboil berth in Waterport. The incident happened at around 11 in the morning. According to eyewitnesses all four were Spanish nationals in their twenties, sailing from Málaga to Algeciras but ran out of fuel and were towed into Gibraltar. Other eyewitnesses reported seeing the semi-rigid zodiac-type vessel foundering. The Fire Brigade believes that an accumulation of fumes combined with a short-circuit caused a low-level flash which provoked severe burns in three of the men, and minor burns in the other. The bottom of the boat caught fire, but the flames were already out by the time the City Fire Brigade attended. The men were treated in St. Bernard's Hospital.