French-backed Malian forces are battling Islamist militants in a key town that leads toward the city of Gao, a militant stronghold in the country's north.
Residents and security officials say French and Malian forces fought rebels in Hombori, on Friday, a town about 250 kilometers from Gao.
Meanwhile, local officials say militants have bombed a strategic bridge near the border with Niger.
A French-led international counter-offensive against Islamist militants who seized control of much of northern Mali last year has entered its third week.
VOA correspondent Idrissa Fall, who is in Mali, says French and Malian forces are pushing toward rebel strongholds.
"They left the city of Diabaly, which they had taken last week, and are now going north, past a city called Nampala, which is very close to Mauritania, and heading to Lere, which is also very close from the Mauritanian border. And, from Lere there is a small airport there and the French troops are within, let’s say, 100 or 200 to Timbuktu," Fall reports.
The French troops will gradually be replaced by West African soldiers who are moving into Mali.
The rebels imposed a strict interpretation of Islamic law on the region. Also, their presence has raised fears that northern Mali could become a haven for terrorists.
Also Friday, the United Nations refugee agency made an urgent appeal for international aid to help hundreds of thousands of people displaced by Mali's unrest.
At a Geneva news conference, UNHRC spokeswoman Melissa Fleming said the large number of people internally displaced by the fighting is putting a strain on resources in cities including the capital.
"In Bamako, we now have a number close to 50,000 people who have taken refuge in the capital. They are in very poor neighborhoods with little or no access to housing or clean water, education and health,'' Fleming explained.
In another development, a faction of one of the armed Islamist groups occupying northern Mali has announced it has broken away to form its own movement.
A portion of the Ansar Dine rebel group said Thursday it had formed the Islamic Movement for Azawad. The new group expressed a willingness to seek a negotiated solution to the country's crisis.
Separately, the head of the U.S. African Command (Africom) said the U.S. forces that trained Malian troops focused on tactical and technical matters but may not have spent enough time focusing on "values, ethics and military ethos."
General Carter Ham commented after human rights groups said Malian troops had been involved in executions and other abuses.