TRIPOLI (Reuters) - A Libyan official said six guards were killed in an airstrike on Friday on a pipeline production plant just south of Brega in eastern Libya."This will be a major setback to future projects and a great problem to the maintenance activity," Abdul Hakim el-Shwehdi, managing director of Libya's state al-Nahr company which runs the country's giant irrigation project, told reporters in Tripoli. (Reporting by Missy Ryan; Writing by Giles Elgoodl editing by Tim Pearce)
