The recent assassinations of Guinea-Bissau’s president and army chief have cast a deep uncertainty over Senegal’s restive Casamance region, where a decades-long separatist struggle has been heavily influenced by Bissau politics, analysts say.

On 2 March President João Bernardo Vieira was shot dead, hours after a rocket attack killed Army Chief of Staff Tagme Na Wai. Guinea-Bissau officials have insisted the presidential assassination was not a coup, and on 3 March Guinea-Bissau swore in the parliament speaker Raimundo Pereira as interim leader and insisted it will maintain civilian rule.

Guinea-Bissau in the 1990s served as a rear base and arms supplier for Casamance rebels – who launched a separatist movement in 1982 – but since 2000 the country’s support of the Senegalese government has been a critical factor in the relative calm in Casamance, according to Martin Evans, lecturer in international development at University of Chester and an expert on Casamance.

“Calm in the Guinea-Bissau border area has been the biggest factor in allowing people to return to their home villages,” Evans told IRIN. “There is not the constant supply of arms to and threat from MFDC [Movement of Democratic Forces in Casamance] guerrillas in Guinea-Bissau.”

Years of low-level fighting in Casamance has displaced tens of thousands of people. The Internal Displacement Monitoring Centre says given patterns of population movements in the region a definitive number is hard to come by, and that estimates of currently displaced range from 10,000 to 70,000.

When he came to power in 2000 Guinea-Bissau then-President Koumba Yala was supportive of Senegalese President Abdoulaye Wade's early attempts to resolve the Casamance conflict, saying he would not allow Guinea-Bissau to be a support base for the MFDC.

This stance has held in Guinea-Bissau since. "As several observers have noted, relative calm in Casamance in recent years has been less about the Senegalese government's negotiating prowess and more about political dynamics in Guinea-Bissau,” Evans told IRIN.

The two countries are intimately linked, he said, noting that Guinea-Bissau’s 1998-99 civil war was largely a proxy war for the Casamance conflict, with MFDC and Senegalese troops coming in to support opposing sides.

Oumar Diatta, Casamance-based writer and specialist on the region, said the death of Vieira and Na Wai “could lead to an overhaul in Casamance that would favour [MFDC hardliners]” who had been weakened by Guinea-Bissau’s support for the Senegalese government.

“The developments in Guinea-Bissau could raise tensions in Casamance,” he said. “All will depend on what the Senegalese government does.”

Despite Guinea-Bissau’s insistence that calm and civilian rule will be maintained, uncertainty abounds.

“Na Wai and Vieira were partners in peace in Casamance,” Senegalese political analyst Babacar Justin N’diaye told IRIN. “We do not know their successors’ policy yet.”

In a volatile, drug-trafficker-infested region, Senegal is surrounded by countries where civilian governments have been upended.

Read IRIN reports on Guinea and Mauritania coups.

“For some time Senegal has been sandwiched between military regimes,” Ndiaye said. “Mauritania, and the two Guineas in the south…The only democratic air [Senegal] is able to breathe is via Mali and across the Atlantic. This is why Senegal feels it has to be a geopolitically strong player in Guinea-Bissau’s unfolding situation.”

Interim leader Pereira has vowed to hold elections within 60 days in accordance with the constitution.

University lecturer Evans said: “One hopes that whoever ends up in power in Guinea-Bissau will pursue the same sort of policy Yalla and Vieira had, of cooperation with the Senegalese government.” He added: “Yet more instability in Guinea-Bissau can only make the cross-border cooperation – essential in supporting peace in Casamance – more difficult."

IRIN