Harare - Emmerson Mnangagwa, who was removed by Zimbabwe's leader Robert Mugabe as vice president on Monday after a bitter tussle with the first lady over succession, had waited almost four decades for his chance at the top job.Nicknamed "Ngwena" (The Crocodile) because of his fearsome power and ruthlessness against rivals, the 75-year-old had a reputation for taking no prisoners.But he was ultimately outfoxed by Grace Mugabe, who is 41 years younger than her husband, after she apparently convinced the veteran head of state to ditch his long-serving minister.An acrimonious weekend in which Mugabe's wife was openly booed at a rally prompting the president to blame Mnangagwa, who was present, probably sealed the fate of the outgoing number two. It was the climax of long-running tensions between the first lady and Mnangagwa.Analysts have suggested that Mnangagwa's sacking would effectively disqualify him from the race to eventually replace Mugabe, now aged 93.Political wilderness In the early days after independence from Britain in 1980, Mugabe made the young lawyer his minister for national security. Since then Mnangagwa has occupied a host of cabinet positions but relations between him and his political mentor have not always been cosy and the younger man is no stranger to presidential purges. In 2004 he lost his post as the secretary for administration in the ruling Zanu-PF party after being accused of openly angling for the post of vice president.Four years in the political wilderness followed, during which his then rival Joice Mujuru became vice president and the favourite to succeed Mugabe. She was ultimately deposed following a campaign orchestrated by Grace Mugabe who convinced the president she was not to be trusted.Political comeback The 2008 elections, when he was made Mugabe's chief election agent, changed Mnangagwa's fortunes.Mugabe lost the first round, but his supporters were not going to make the same mistake in the second round, which was marred by violence, intimidation and allegations of vote rigging.In the same year Mnangagwa took over as head of the Joint Operations Command, a committee of security chiefs, which has been accused by rights groups of organising violent campaigns to crush dissent.He was targeted by EU and US sanctions imposed on Mugabe and his close allies over the elections and violence, but promptly given control of the powerful defence ministry.It was a return to the home that made him a force in Zimbabwean politics in the first place.Anti-colonial fighter Born in the southwestern Zvishavana district on September 15, 1942, he completed his early education in Zimbabwe before his family relocated to neighbouring Zambia.His grandfather was a traditional leader and his father a political agitator for the repeal of colonial laws that disadvantaged blacks.In 1966, Mnangagwa joined the struggle for independence from Britain, becoming one of the young combatants who helped direct the war after undergoing training in China and Egypt.He was part of a group that carried out several raids against government facilities, including blowing up a train near the southeastern town of Masvingo.He was arrested and sentenced to death but his sentence was later commuted to 10 years in prison because of his young age.'Destroy and kill' After independence in 1980, he directed a crackdown on opposition supporters that claimed thousands of lives in the Matabeleland and Midlands provinces.His role in the crackdown, stern demeanour and uncompromising language earned him a fearsome reputation.He once remarked that he had been taught to "destroy and kill" -- although he later claimed to be a born-again Christian. "How this will end will be dependent on the reaction of Mnangagwa's allies, the army and Mnangagwa himself. Whatever the outcome we hope this does not degenerate into anarchy," said Takavafira Zhou, a political analyst at Masvingo State University, following the firing.Zhou previously described Mnangagwa as "a hardliner to the core"."He calls himself soft as wool and wants to portray himself as a soft and diplomatic person but the truth is he is a hardliner," Zhou told AFP.Mnangagwa will apparently not need to worry about his income after being fired from government.A US diplomatic cable published by WikiLeaks in 2008 claimed Mnangagwa had amassed "extraordinary wealth" during Zimbabwe's 1998 intervention in gold and diamond-rich Democratic Republic of Congo.