Six people including Hilda Hernandez, sister of Honduras President Juan Orlando Hernandez were killed in a helicopter crash on Sunday on a mountain near the country's capital.
Hernandez, 51, was an agronomy engineer who served as communications minister under her brother and as minister of social development during the previous administration of then-President Porfirio Lobo.
The military helicopter carrying Hernandez, four members of her security detail and a pilot took off from Tegucigalpa's international airport in the morning bound for her residence in Comayagua, about 60 kilometers from the capital.
Soon afterward, the air force reported that the aircraft had gone missing. The wreckage was later discovered in the mountains outside Tegucigalpa with no survivors.
President Hernandez changed his Twitter profile picture to a black ribbon of mourning.
Reynaldo Sanchez, the head of the president's National Party, said in a statement: "Be with God, Hilda Hernandez, a tireless fighter for our party."
No cause for the crash was given, but it happened as the country was being affected by a cold front. Juan Orlando Hernandez is in the middle of a dispute over Honduras' November 26 presidential election, in which electoral officials say he took 43 per cent of the vote to41.4 per cent for opposition candidate Salvador Nasralla.
Nasralla has alleged fraud and is not recognizing the results, and the Supreme Electoral Tribunal has not yet declared a winner.Â