Egypt's Hosni Mubarak, who was reported clinically dead after suffering a stroke in prison on Tuesday, enjoyed near absolute power for three decades before being toppled by a popular uprising last year.
The official MENA news agency reported that Mubarak was "clinically dead" after "his heart had stopped beating and did not respond to defibrillation."
The 84-year-old had suffered a stroke and been defibrillated before being transferred to hospital from the prison where he has been held since he was sentenced to life over the murder of protesters.
Mubarak had faced the gallows, with the prosecution calling for the death penalty.
After he was flown to Tora prison on Cairo's outskirts after the sentencing, he refused to leave the helicopter and security officials said he "suffered from a surprise health crisis" before they finally convinced him to go in.
His health has fluctuated since then, with doctors defibrillating him twice on June 11. He has reportedly suffered acute depression, as well as periodic increases in blood pressure and shortness of breath.
His was a spectacular fall from grace that sent shock waves across the Middle East and beyond when he announced his resignation on February 11, 2011 after an 18-day popular revolt. The military took power after his resignation.
Until anti-government protests erupted on January 25, Mubarak seemed untouchable as president of the most populous nation in the Arab world, backed by the United States and the military, from whose ranks he had emerged.
Mubarak had survived 10 attempts on his life and his health has long been a subject of speculation. But in the end, it was the people who brought down Egypt's latter-day pharaoh.
He rose to power unexpectedly, when then president Anwar Sadat, who made history by signing a peace deal with Israel, was gunned down by Islamist militants on October 6, 1981 at a military parade in Cairo.
Mubarak took office a week later and ruled without interruption until last year.
Islamic fundamentalist groups, including Al-Jihad, Gamaa Islamiyya and Talaeh al-Fatah, were responsible for most of the attempts on Mubarak's life.
The first came in 1993, a year after Islamists launched a violent campaign to topple the secular government, when a bid to fire rockets at Mubarak's plush Cairo residence was foiled.
Later attempts included a plot to car-bomb the presidential motorcade in Cairo.
In 1995, militants opened fire on the presidential motorcade in Addis Ababa, a year after they tried to kill Mubarak with explosives as he was due to meet Libyan leader Moamer Kadhafi at a military airport.
In September 1999, Mubarak was slightly wounded when a man with no apparent links to any Islamic group stabbed him in Port Said.
With his jet black hair and aquiline nose, Mubarak had a reputation for vigour and was once known to play squash almost daily.
But that was dented in 2003 when he fainted while addressing parliament.
Officials blamed his collapse on a cold and the fact that he had been fasting during the Muslim holy month of Ramadan.
In 2004, he underwent surgery in Germany for a slipped disc, and he returned to Germany in March 2010 for the removal of his gall bladder and a growth on the small intestine.
Rumours that he had died under the knife were dispelled when state television showed him recovering.
Mubarak's health was usually a taboo subject in Egypt and the father of two, whose wife Suzanne is half Welsh, kept his private life a carefully guarded secret.
In 2007, speculation about his health snowballed to the extent that Mubarak made an unscheduled public appearance to lay rumours to rest.
Mubarak was born on May 4, 1928 in the Nile Delta village of Menufiyah.
He rose through the ranks of the air force and fought in repeated wars with Israel, to claim hero status before supporting Sadat in pursuing peace with the Jewish state in 1979.
Throughout his years in power, he maintained the unpopular policy of peace with Israel and accommodation with the West that cost Sadat his life.
His government was the frequent target of domestic opposition -- ranging from the Muslim Brotherhood to secular and liberal dissidents.
But the regime quashed militant groups, which carried out attacks in the 1980s, 1990s and, more recently, in 2004 and 2006, when tourist resorts were targeted.
His ties with the United States and Israel drew criticism from across the region, especially during the 2006 Israeli war in Lebanon and Israel's Gaza offensive in 2008-2009.
Domestic opponents accused Washington of turning a blind eye to human rights abuses, corruption and the Mubarak regime's failure to push ahead with badly needed reforms.