Police launched a murder inquiry yesterday after the eldest son of the President of Chad – until recently considered his political heir – was found dead in the suburban Paris building in which he lived.

Brahim Déby, 27, who had been groomed as a possible successor to Idress Déby, suffered a gash to the head and was discovered in a staircase leading to his block’s underground car park in the west of the capital.

A post-mortem examination later found that he had died of asphyxiation, “probably by the white powder he had been sprayed with.” The powder came from a fire extinguisher found next to his body.

Chadian diplomats quickly said that there was no apparent political aspect to the killing, but rebels who have been waging a guerrilla war in eastern Chad hailed the death as a blow to the ruling clan. President Déby had employed his son as an adviser and appeared to be grooming his as a possible successor until June last year, when he was convicted in Paris of drug and firearm offences.

He was sentenced to a six-month suspended term after being arrested in a fight outside a nightclub in western Paris when he was carrying an unlicensed pistol. Prosecutors accused him of using a diplomatic bag to have the weapon delivered. Police found marijuana and cocaine in a search of his flat. Déby had been investigated in other drug cases, police sources said. His father, a former French-trained helicopter pilot, was told of his death at a summit of African leaders in Accra.

Brahim was widely disliked and his role as his father’s anointed successor had cause a split in the family. His death is a blow to the Zaghawa clan which has ruled the former French colony since Idriss Déby seized power in 1990. President Déby, a close ally of Paris, was reelected to a third term last year. Critics contested the fairness of the elections, as well as those in 1996 and 2001.

A spokesman for the rebel Union of Forces for Democracy and Development said that Brahim Déby had been a key source of resentment who had driven members of the President’s Administration to turn against him. “He is at the root of all the frustration. He used to slap government ministers, senior Chadian officials were humiliated by Déby’s son,” the spokesman said. “They had to leave the regime; go into the bush. They chose the military option instead of being humiliated inside Chad.”

Chad is one of five African countries in which France maintains a military presence. President Sarkozy has promised to break with the indulgence that President Chirac and his predecessors had shown towards the leaders of France’s former colonies.

Last year’s election in Chad followed an attempt by rebels, including members of Mr Déby’s family, to capture the capital. The insurgents staged the attack from bases in the volatile region where borders on Darfur.

Chadian rebels have suspended hostilities with government forces in the eastern part of the country while their leaders attend peace talks in Tripoli, brokered by Colonel Muammar Gaddafi, the Libyan leader. However, they say that they will resume hostilities if the talks fail. The rebels want President Déby to agree to a national political dialogue that would lead to a transitional administration and then free elections. They also want the constitution amended to prevent presidents from ruling for life.

War and invasion

— After independence from France in the 1960s Chad endured three decades of civil war and Libyan invasion. There is sporadic rebel activity in the North and it is currently negotiating with rebel groups on its eastern border

— 80 per cent of the 9.8 million population relies on subsistence farming. Oil sector exports began in 2004 after foreign investment

— President Déby, leader of a 1990 coup, returned to office in a series of flawed elections and removed constitutional limits on presidential terms in 2005

Source: CIA World Factbook; Times archives

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