"We are continuing our sweeping operations on the ground," said an officer in Bignona, about 30 kilometres Ziguinchor, the main city in Casamance.
On Monday, firefights broke out there between the army and suspected members of the MFDC (Movement of Democratic Forces of Casamance), the independence movement in the southern region.
The army’s communications department, Dirpa, said in a statement that soldiers had faced "one hundred rebels who wanted to enter" Bignona.
"These clashes resulted in the deaths of seven soldiers, including four by accident. The rebels suffered heavy losses, with many wounded,” said the statement. A Dirpa source told the AFP news agency the four killed by accident died when a vehicle overturned.
The army said Tuesday that the MFDC seems to be better equipped than before.
"It is certain that they have new equipment which they did not have before, such as rocket launchers, mortars and machine guns," an army official said, adding that the rebels "now have enough ammunition."
"The weaponry used by the rebels in Casamance has raised questions within the military hierarchy,” reported the local newspaper Le Quotidien. “It has been discovered that the guerrillas are using heavy artillery and are shelling the same way as the army.”
Senegalese officials suspect that neighbouring countries are helping the separatist group get armed. A cache of Iranian arms that was discovered in October in Legos, Nigeria, on its way to Gambia, raised fears in Senegal that they were destined for the MFDC.
Senegal recalled its ambassador to Tehran in mid-November in protest.
Security forces fear that the MFDC is planning on stepping up its operations in the coming days as it prepares to mark the anniversary of the outbreak of the separatist rebellion in December 1982.
Sporadic outbreaks of violence have continued in Casamance since a peace deal was signed in 2004.