In a statement, it said that officials were looking into "among other things, matters relating to the attribution ot golden visas and suspicions of the crimes of corruption, graft, embezzlement and money laundering."


The searches are beeing carried out at the offices of various state institutions, including the secretariat of state of fiscal affairs, the immigrant and border agency SEF, the Ministry of Finance, among others, as well as a number of private residences.


As part of Operation Labyrinth, the investigation into suspected corruption in the administration of the government's 'golden visa' programme to fast track residence for major investors, 11 people have so far been detained as part of that operation, including several senior civil servants.


In a statement earlier on Wednesday, the Ministry of Finance said that the action being carried out by prosecutors at the secretariat of state for fiscal affairs related to "the tax treatment, for VAT, relative to a transaction between a Portuguese company and the Libyan Ministry of Health." It said the secretariat was ready to collaborate with the investigation.


Portugal and Libya in 2013 signed an agreement that provided for hundreds of Libyan citizens, including injured members of the military, to receive medical treatment in Portugal, and for Libyan health professionals to be given training in the country.


In comments to Lusa at the time, the deputy president of the Luso-Libyan Association, Luís Cabrita, said that the patients would initially be treated in private health institutions, although public hospitals could also be involved.