HOW DID YAYA DILLO DIE?

The Chadian government has said Dillo was killed in an exchange of gunfire with security forces on Feb. 28. It said members of his Socialist Party Without Borders had earlier attacked the internal security agency.

But the FACT opposition rebel group and the CNRD opposition party have called it an assassination and analysts say the circumstances are unclear.

WHAT IS HAPPENING IN CHAD?

The capital N'Djamena was quiet two days after the death, though residents said security forces were deployed in key locations and soldiers searched for weapons at checkpoints overnight. Access to the internet has been cut.

Dillo's death comes at a politically sensitive time as Chad prepares for presidential elections in May and June.

The votes were meant to draw a line under three years of military rule by transitional President Mahamat Idriss Deby, who seized power after his long-ruling father was killed in clashes with rebels in April 2021. 

Deby junior, who is standing in the vote, has since faced street protests against delays in the elections and has had to bring some members of the opposition into his government, under moves to ease tensions brokered by regional leaders.

The United Nations and regional leaders have called for calm and urged Chadians to focus on the vote.

DIVISIONS IN THE RULING ELITE

The violence this week has further exposed the complex ethnic and family ties that make up Chadian elite politics.

Deby senior had concentrated military and political power around his Zaghawa ethnic group. His son has struggled to maintain that unity, and divisions have emerged, with some family members openly opposing him.

Dillo, the opposition leader who was killed, is from the same clan - believed to be a cousin or nephew of Deby junior - and his death has triggered anger within the family. Exacerbating these concerns, the transitional president's uncle, General Saleh Deby Itno, last week defected to Dillo's party and was reportedly subsequently detained.

Roland Marchal, a Chad expert at the Centre for International Studies (CERI) at Sciences Po Paris, said the fact that Saleh joined Dillo's party was a signal that some in the extended family were extremely unhappy.

"The killing of Dillo is a sign of weakness. Yaya Dillo is not very popular in Chad so why take such extreme measures against him?" Marchal said.

Security sources say Deby junior has sought to stamp his authority on the security forces, including by creating new units loyal to him.

WHY IS CHAD IMPORTANT TO THE WEST?

As Islamist militancy spread across much of West Africa during the last decade, Chad has established itself as a key partner for Western and regional militaries.

Former colonial power France still has 1,000 troops and war planes based there, even as it has been forced to withdraw from Mali, Niger and Burkina Faso due to rising anti-French sentiment in the region.

The United States has had drones based in Chad. N'Djamena also hosts the headquarters of the regional counter-terrorism task force.

Positioned between Libya and Sudan, Chad's remote borderlands are often used by smugglers and armed groups operating in regional conflicts. 

Most recently, United Nations experts said that Chad has been used as a route to supply crucial weapons from the United Arab Emirates to the RSF, the militia that has been fighting the Sudanese army since April last year. The UAE denies this. Chad hosts nearly 700,000 Sudanese refugees from this conflict.

(Reporting by David Lewis; Editing by Andrew Heavens and Crystal Chambers)

By David Lewis