The Malian military has gained control of the central town of Diabaly, a key advance in the battle against Islamist militants in the north.

The country's forces retook the town without ground assistance from French troops, a military spokesman said. The French military confirmed that it provided only air support.

French officials said Malian forces pushed the Islamists into the forest beyond Diabaly.

Rebel control over Diabaly was one of the chief concerns to Mali and France as they tried to stop the Islamists' movement into the south. French involvement began after militants said January 10 that they had seized another town, Konna.

French and Malian forces retook the key town of Konna from militants Friday, a French source said. Gunfire could be heard in the town Monday.

In the town of Sevare, roads were cordoned off and journalists restricted as battles raged.

As fighting continues, many people are being cut off and in need of basic supplies.

France is considering sending more troops to assist the Malian military.

The number could top 2,500, French Defense Minister Jean-Yves Le Drian said Saturday. There are about 2,000 French troops in Mali so far, he told CNN affiliate France 3.

French President Francois Hollande said the offensive's mission is to destroy the terrorist groups that have taken root.

West African leaders are also discussing possibilities for additional forces. Regional leaders met Saturday in the Ivory Coast capital of Abidjan to discuss speeding up deployment of troops.

The regional bloc -- the Economic Community Of West African States -- has said it has 3,300 regional troops on standby.

It urged the United Nations to provide immediate logistical and financial support for African troops.

"The escalation of conflict in recent days reminds us the importance of assuming our responsibilities very quickly in a dynamic of coordination with our partners," said Charles Koffi Diby, the Ivory Coast foreign minister. "We should act very quickly."

Mali was relatively stable until a coup last year toppled the president. Islamists capitalized on the chaos and established themselves in the north.

They imposed a strict interpretation of Sharia law, banning music, smoking, drinking and watching sports on television. They also damaged historic tombs and shrines.

On Saturday, demonstrators in the city of Gao killed the chief of Islamic police, who was imposing Sharia law on behalf of the Islamists.

A day earlier, Islamist militants killed local journalist Kader Toure for allegedly giving information to the Malian army. The journalist was shot while on his motorcycle, a witness told CNN.

Demonstrators in Gao avenged the reporter's death on Saturday by killing police chief Aliou Maiga, an eyewitness said.

'It was absolutely necessary'