Two people have died following the collapse of a stage being constructed for a Madonna concert in France. A 53-year-old French worker was killed outright in the accident, which took place at around 17:15 (15:15 GMT). Whiles a 23-year-old British man who had been in intensive care on a neurosurgery ward in Marseilles died overnight. Technicians had been setting up the stage at the city's Velodrome stadium when the partially-built roof fell in on Thursday, bringing down a crane. Madonna said she was "devastated" by the news. Her concert, planned for Sunday, has been cancelled. Eight other people were seriously hurt, including an American who was hospitalised in a life-threatening condition. More than 30 people suffered minor injuries and shock, according to authorities. The 60,000-seater Velodrome is France's second-biggest sports arena and home to the Olympique de Marseille football club. Fire-fighters said the accident occurred when the roof of the stage became unbalanced as it was being lifted by four cranes, toppling one of them. About 50 people from a range of nationalities were working to set up the structure, city sports official Richard Miron said. The roof "started shaking and collapsing" gradually, said Marseilles city councilor Maurice Di Nocera. "Since it did not collapse right away that allowed several people to get out," he said. Madonna, who is performing on her Sticky and Sweet tour, was in Udine, Italy, when she was told of the incident. "I am devastated to have just received this tragic news," she said in a statement released by Live Nation, the organisers of the concert. "My prayers go out to those who were injured and their families, along with my deepest sympathy to all those affected by this heartbreaking news." Source: BBC