A father-of-five is critically ill in hospital in Palma after developing a blood clot in his leg. Gary Gibson, from Glasgow, was on holiday in Magalluf with his wife, Lillian, and their children when he became ill. The 37-year-old was admitted to hospital on December 2, the day before his family were due to fly home and doctors operated on his right leg after they discovered a deep vein thrombosis, commonly known as economy-class syndrome. Mr Gibson remains critical in a Palma Hospital, a Foreign Office spokesman said. His family have since returned to Glasgow. They are understood to have gone on holiday without travel insurance. The Foreign Office spokesman said: The clot has been removed from Mr Gibson's leg, but there have been complications since then. He has since developed pneumonia and kidney failure. He remains in a critical condition and is under sedation. The spokesman said consular staff in Majorca were in touch with medical staff at the hospital on a regular bases. A recent study has discovered that one in every 100 travellers on flights of four hours or more develop blood clots. Researchers in New Zeland tested blood samples from a thousand 18 to 70-year-olds after flights of four hours or more and found 14 blood clots while many lacked any obvious risk factors when assessed before flying.