Out of 5 three were assassinated while one died Mysteriously and other died of health related issues, the longest to stay in office among the dead leaders was tafawa balewa who ruled for six years before he was killed by military coup. The shortest was aguyi Ironsi who ruled for only few months before assassination.
• Let start with late Abubakar tafawa balewa (prime minister)
Lived from 1912-1966 he was the first Nigerian head of government to die in office, he was appointed prime minister of the nigerian federation in 1957 and after Indefendence in 1960, he remained in that post he ruled the country till January 15, 1966 when he was kill In the first military coup in the country, He was a founder and Deputy President of the northern Peoples Congress.
• The 2nd Is Late Major General Johnson Thomas Ummunnakwe Aguiyi Ironsi
Live from 3rd march 1924 -29 July, 1966 He was a nigerian who siezed power in the chaos that ensured in the first military coup in Nigeria. He served as the head of state in nigeria from 16 january, 1966 untill he was Overthrowed and Killed.
• And the 3rd Is Late General Murtala Ramat Muhammad
He was born on november 8th 1938 and dead on feb. 13th 1976, Murtala was served as Head of State in July, 1975 when gen. Gowon was over thrown while at an Organization of African Unit (OAU) summit in kamfala, Uganda, He was killed at age 37 alongside his aidede-camp, Lieutenent Akintunde Akinsehinwa, on feb, 13th 1976 in an abortive coup attempt lead by Lt.col. Buka Suka Dimka, when his car was ambushed while enroute to his office at Dodan Barrack Lagos.
• The 4th Is Late General Sani Abacha
He was a Nigerian army General And Politician, who served as the defacto President of Nigeria from 1998 to 1998.Abacha died mysteriously in june 1998 while at Presidential villa in Abuja and was Buried on thesame day, According to Islam Law.
• The 5th Was Late Umaru Musa 'Yar'Aduwa
He was the President of Nigeria and he was decleared winner of the controversial Nigerian Presidential election held on 21st April 2007, and was sworn on 29, may, 2007 then he left nigeria On 23rd Nov. 2009 to Saudi Arabia where he was reported to be receiving treatment for pericarditis On 24 Feb. 2010 then he returned to Abuja and his health was unclear. He eventually died on 5 may at Aso Rock Presidential villa. An Islamic Burial took place in his home.