An accident at Palazzo delle Esposizioni, one of Rome's largest exhibition spaces, injured seven people who were working on the renovation of the building. Two are in a serious condition. The incident occurred on 14 September and is thought to have been caused by the excessive weight of building material on the roof. The new roof, to be made of slabs of crystal, was part of the 19 million restoration campaign for the building. It is still hoped that the PalaExpo, which was due to hold its first exhibition at the end of this year, will open sometime in 2005.