German Chancellor Angela Merkel on Friday backed her popular defence minister, Karl-Theodor zu Guttenberg, who has come under criticism in recent days over a series of military embarrassments, dpa reported. Guttenberg's office has most recently been accused of mishandling information on the death of a soldier in Afghanistan last month, when it emerged that he had been killed by the gun of a comrade. Earlier in the week, rumours of a mutiny following a fatal accident on board the navy's training ship Gorch Fock led Berlin to recall the vessel to port in Argentina, where it was sailing. Additionally, Guttenberg has come under fire over claims this week that letters soldiers' post to their families from Afghanistan was being "systematically" tampered with. All this emerged as Germany was fixing the terms of its military mandate in Afghanistan, where Guttenberg has advocated a fixed target date of late 2011 to begin troop withdrawal. The developments could taint the image of Guttenberg, who rose rapidly within the Bavarian Christian Social Union allied with Merkel's Christian Democrats to become one of Germany's most popular politicians. Merkel, however, was "certain that this excellent defence minister, who takes his responsibility towards the soldiers just as seriously as his duty to parliament and the public, will achieve his duties," her spokesman Steffen Seibert said on Friday. Earlier in the day, Guttenberg said he "nothing to reproach myself for," regarding the death of the soldier in Afghanistan, and insisted he had correctly informed the public the following day. The defence ministry said it was unable to comment on reports that the soldier was "playing" with his gun at the time of the accident. At the same time, a spokesman admitted that the ministry had delayed in handing Guttenberg a military police file on the incident. Apparent failures in internal defence ministry communication were reminiscent of events in 2009 surrounding a fatal bombing of two fuel trucks in Afghanistan, a scandal that eventually cost Guttenberg's predecessor Franz Josef Jung his position in government. The event has prompted questions over Guttenberg's command of the Bundeswehr, or military. Meanwhile, a team of investigators was due to question the crew of the Gorch Fock in Argentina next week. As well as rumours of mutiny, allegations have surfaced that officers sexually abused a trainee. The death of the female crew member who fell from the ship's rigging in November is one of several fatal injuries that have occurred on board the navy training vessel in recent years. With regards to military post from Afghanistan, Defence Ministry spokesman Steffen Moritz said 15 soldiers had come forward during the investigations with claims that a total of 20 letters had been tampered with. It emerged that a private, possibly Afghan, supplier was transporting military post from the restive province of Baghlan to the German headquarters in Masar-i-Sharif. The parliamentary ombudsman for the military, Hellmut Koenigshaus, asked whether there were underlying reasons for the recent spate of incidents. "It needs to be examined whether the leadership has failed," Koenigshaus told daily Passauer Neue Presse. Guttenberg rejected the allegation. "If the allegations turn out to be true, then it would probably be a case of individual misconduct," the minister told daily Sueddeutsche Zeitung. -- SPA