A woman has been injured by a parcel loaded with explosives that was posted to the International Monetary Fund (IMF) offices in Paris.
It detonated as she opened the package, burning her hands and face in a blast that caused the building to be evacuated and put on a security lockdown.
The device was intended for the IMF's European representative, Jeffrey Franks, who has been in his post since March 2015 after 24 years at the institution.
Investigators said it was comprised of a “large black cylinder, about 30cm long”, with the blast radius so large the room's ceiling was hit by shrapnel.
French police described the device as a “big firecracker” that appeared to be homemade.
The attack bore all the hallmarks of a Greek anarchist group known as the Conspiracy of Fire Cells (Synomosia Pyrinon Tis Fotias), which claimed responsibility for another package bomb sent to the German finance ministry on Wednesday.
Police in Berlin said the device, which was safely intercepted before it reached Wolfgang Schäuble, contained explosive substances commonly used in fireworks manufacturing and was designed to cause severe injuries when opened.
Greece's interior ministry said the item had a Greek stamp and was falsely sent under the name of a right-wing New Democracy party politician.
An investigation is underway into how the explosives bypassed Greek security checks to leave the country.
Conspiracy of Fire Cells militants claimed responsibility for the attack, saying it was part of their “Nemesis” operation in revenge for the imprisonment of activists.
Founded during the 2008 financial crisis, the designated terrorist group has carried out waves of fire bombings and a high-profile parcel bomb plot in 2010, where devices were sent to targets including Nicholas Sarkozy, Angela Merkel, Silvio Berlusconi, European embassies and Europol.
Police crackdowns have resulted in a series of arrests and prosecutions but a message posted online on Thursday claimed the group’s “comrades” would continue their violent struggle.
“For each comrade in prison, new comrades are ready to take his place and continue the path of attack,” said a Conspiracy of Fire Cells statement, signed off with the phrase “LONG LIVE ANARCHY”.
“We sent parcel bomb to the German finance minister as part of the second act of the Project Nemesis campaign.
“Watch for more announcements in the future.”
There was no immediate claim for the attack on the IMF, which followed previous targeting patterns focusing on authorities and countries linked to Greece’s controversial bailout programme.
Francois Hollande, who was on a visit to the south of France near Toulon, said the package bore "a similarity with another event of the same nature in Berlin”.
“We are trying to establish the causes of what happened as part of an international investigation,” the President added, calling the incident a new attack on France and vowing that those responsible would be found.
Mr Hollande said: “We are again confronted with an attack. There is no other word for it when you are confronted with a package bomb.
“I want to tell all those who work for this great institution that we are by their side.”
Michel Cadot, the chief of Paris police, said the injured secretary's hearing was also affected and that she was receiving treatment.
Asked if Mr Franks had received threats, he added: “There had been some phone calls in recent days but they don't seem necessarily to be linked to this matter.”
France’s anti-terrorism branch opened an investigation into attempted murder, destruction through explosive means, possession of explosive substance and links with a terrorist initiative.
IMF director Christine Lagarde, who is on a trip to Germany, said French authorities would ensure the safety of its staff.
“I condemn this cowardly act of violence and reaffirm the IMF's resolve to continue our work in line with our mandate,” she said.
France remains on high alert following a series of Isis-linked terror attacks that have sparked an ongoing state of emergency.
Thursday's explosion came just hours before a student opened fire at a school in Grasse, where authorities said there was no immediate link to terror.
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