Senegalese refugees in Guinea-Bissau who had recently returned to their homes in Senegal’s Casamance region on Monday were fleeing back across the border following four days of fighting.

“There was heavy fighting with a large number of Senegalese and Moroccan troops coming into our village and we didn’t feel safe anymore,” said Matar Badji, who arrived with 30 family members in the Guinea-Bissau village of Ndindjim, 5km from the border.

The Senegalese army said about 500 Moroccan troops are in Casamance to assist with a de-mining operation to help make the region safe for the return of refugees. Often in Casamance, where a rebellion has simmered since 1982, just the appearance of Senegalese troops can trigger flight because residents fear combat is imminent.

Badji said fighting began on Thursday morning between Senegalese forces and local rebels who had controlled the area since March. He said he saw heavy weapons fire and aerial bombing.

“Everyone has now left my village,” he said. “It is completely empty again.”

In recent months, thousands of Senegalese refugees who had been in Guinea-Bissau for up to 10 years started returning to their villages in the Casamance following signs that the 2004 peace agreement between the Senegalese army and two factions of rebel Movement of Democratic Forces of Casamance (MFDC) was holding.

Last March the MFDC faction led by Cesar Badiate worked together with the Guinea-Bissau army to oust the one remaining faction led by Salif Sadio, which has not signed the peace agreement. Sadio’s group had been based in southern Casamance near Guinea-Bissau but has since fled to northern Casamance near The Gambia.

On Monday Badiate told IRIN he did not understand why the Senegalese army was allegedly attacking him.

“According to the peace agreement the Senegalese army must inform us before taking any military action” Badiate said. “Now the agreement is nullified; we will return to war.”

Senegalese army spokesman Antoine Wardini said the only reason Senegalese troops had come into the area that Badiate controlled was to de-mine it. “It was the rebels that attacked us,” he said.

Witnesses have reported seeing Badiate’s forces moving freely across the border into Guinea-Bissau and say some of his rebels have joined the Guinea-Bissau army.

On Friday Guinea-Bissau sent at least two truckloads of troops to the border area. Guinea-Bissau’s chief army commander of the northern military region, Col. Antonio Indjai, told IRIN on Monday that the troops were there to reinforce the border. “We want to reassure local Bissauans near the border that the Senegalese will not cross into our territory,” he said.

When Senegalese troops entered Guinea-Bissau in 1998 to support the government during a brief civil war, thousands of people were killed and tens of thousands displaced.