(ANSA) Naples, January 26 - Magistrates have sent Campania regional governor Vincenzo De Luca a judicial letter informing him that he is under investigation regarding possible irregular official procedures in planning permission for a huge new square in the port of Salerno, judicial sources said Tuesday. The case dates back to when De Luca was mayor of Salerno and finance police also delivered letters to several other people being probed in connection with the Piazza Libertà project. The project was part of an ambitious and costly urban renewal plan for the southern city's Santa teresa district that involved the demolition of a hotel to make space for the piazza. The project remains controversial and has been opposed by environmentalists concerned over the impact on the bed of the river Fusandola that flows through the area. The project will take at least another 18 months to complete.