In a statement, the office said that "searches of 16 homes are underway as part of an inquiry directed by the MP in which various IT attacks are being investigated – including the most recent on 25 April of 2016."

The premises being searched are in various parts of the country, but above all Greater Lisbon.

“At issue are the crimes of illegitimate access (Article 6.º, n.º 1, 2, 3 and 4, line a) of the Law Cyber-crime), of IT damage (Article 4.º, n.º 1 and 3 of the Law on Cyber-crime), of IT sabotage (Article 5.º, nº 1 and 5, line b) of the Law on Cyber-crime) and also criminal association (Article 299.º of the Penal Code)”, the statement says.

The investigation is covered by judicial secrecy, the statement notes.

Earlier, a PJ source told Lusa that the searches began at 7.30am in various parts of the country, including Lisbon and the north of Portugal, as part of an investigation relating to attacks on state information systems.

In February of last year the PJ detained eight people aged between 17 and 40 for information piracy. They were suspected of practising the crimes of sabotage of information systems, damage to information systems, illegitimate access and undue access to various state IT systems, as well as to the systems of private companies.

The detentions took place after the PJ in Lisbon carried out various searches nationwide of so-called 'hacktivists'.

At the time a police source told Lusa that the searches were of premises of suspects linked to the organisation Tugaleaks, a Portuguese organisation inspired by Wikileaks. The detainees were resident in the Greater Lisbon and Porto areas, and belonged to Anonymous Portugal and other related groups.

According to the PJ, the investigation began in April of 2014.