International Monetary Fund chief Christine Lagarde condemned an explosion at the IMF's Paris office on Thursday as "a cowardly act of violence."
The explosion, after a letter was opened, "caused injuries to one of our staff," Lagarde said in a statement.
"I condemn this cowardly act of violence and reaffirm the IMF's resolve to continue our work in line with our mandate. We are working closely with the French authorities to investigate this incident and ensure the safety of our staff," she said.
The Paris police department said the explosion was was caused by a homemade device.
"It was something that was fairly homemade," police chief Michel Cadot told
Cadot said there had been some telephone threats made in recent days, but it was not clear if these were linked to the incident at the IMF's offices.
President Francois Hollande said French authorities would do all they could to find those responsible for the incident.