ROME (Reuters) - An Italian anarchist group on Friday claimed responsibility for parcel bombs sent to offices of national newspaper La Stampa and an investigative agency this week.
A CD carrier case containing powder and cables was sent to the newspaper in Turin on Tuesday, but did not explode due to a malfunctioning detonator.
A similar package that also did not explode was discovered at the Europol Investigazioni in Brescia agency on Wednesday.
In a letter to Genoa-based newspaper Il Secolo XIX on Friday, a group calling itself the Informal Anarchist Federation (FAI) claimed it had sent the packages.
Police could not confirm the authenticity of the letter, published on Il Secolo's web site, but noted that FAI was the same group which claimed responsibility for the shooting and wounding of an Italian nuclear engineering executive last year.
In the letter, entitled "Operation Hunt the Spy" FAI said the two parcel bombs were a continuation of a campaign it had started with the attack on Roberto Adinolfi, chief executive of Ansaldo Nucleare.
Adinolfi was shot in the leg on May 7, 2012, by two men on a motorbike outside his Genoa home. Italian police in September detained two men in connection with the shooting.
FAI said in the letter it had targeted the investigative agency because it was supplying tools such as microphones and micro-cameras to help police spy on members of the group and build up evidence to use against them.
It dedicated the actions to its "friends" in detention, mentioning the first names of the two men held in September, Nicola Gai and Alfredo Cospito, among others.
FAI also criticized La Stampa, saying it is "one of the many newspapers of the regime, therefore every hack is a potential target of our war against the state and the society which supports and legitimizes it every day".
The group has previously claimed responsibility for similar parcel bombs sent to banks, embassies and tax collection offices. Its actions have raised concerns of a possible return to the political violence widespread in Italy in the 1970s.
(Reporting by Catherine Hornby and Sara Rossi; Editing by Jon Hemming)