A helicopter operated by the European Union peacekeeping force in Bosnia and Herzegovina crashed during a routine training exercise in the country’s north on Friday, killing four personnel on board and injuring 11 others, according to a statement from the force.The Italian CH-47 Chinook helicopter crashed in an area near the town of Brcko. The injured personnel are in stable condition and receiving medical treatment, the EU Force (EUFOR) said.Photographs published by the Klix news portal showed the wreckage of the helicopter, which appeared to be largely destroyed and lying on a lawn.EUFOR said a “thorough and complete” investigation into the crash was underway and that further information would be released later. It also clarified that “no civilian infrastructure, property, or vehicles were damaged, and there were no injuries to civilians.”EUFOR’s 1,200-soldier mission took over from NATO in 2004 to maintain security in Bosnia and oversee the military provisions of the peace agreement that ended the 1992-95 war. The mission operates under a United Nations Security Council mandate.