Lebanon's military tribunal on Thursday charged seven people over an attack last month that killed one Irish soldier serving in a United Nations peacekeeping force, three Lebanese judicial sources told Reuters.  On Dec. 15, a vehicle driven by troops from the United Nations Interim Force in Lebanon (UNIFIL) was fired on as it travelled in southern Lebanon.  Private Sean Rooney, 23, was killed in the incident, the first fatal attack on UN peacekeepers in Lebanon since 2015.  The Lebanese military in late December detained one suspect, a supporter of Hezbollah, the armed group that controls the southern part of Lebanon where the attack took place.  He has been charged with murder, according to one judicial source. The other six suspects face charges ranging from attempted murder to damaging a vehicle. None are in custody.  After issuing its charges, the military tribunal transferred the case to a civilian court, Lebanon's army said in a statement.  Hezbollah has officially denied involvement in the incident, calling the killing an "unintentional incident" that took place solely between the town's residents and UNIFIL.  On Dec. 16, Ireland's then-foreign and defense minister Simon Coveney told state broadcaster RTE that he did not accept Hezbollah's assurances that it had no involvement.  UNIFIL has operated in Lebanon since 1978 to maintain peace along the border with Israel and was expanded by the UN resolution that halted the 2006 Israel-Hezbollah war in southern Lebanon.