The two are among the armed groups that seized control of the northern half of Mali, an area the size of France, earlier this year. They fell out earlier this month because MUJAO and another Islamic faction want to impose Shariah law in northern Mali, while the NMLA wants to create a secular country. Last week an unwed couple in Gao was publicly lashed.
Toure said that heavy shooting could be heard until 2 p.m. local time. When he emerged from his house he found that the balance of power in the town had shifted.
"I saw five dead NMLA fighters whose bodies had been dumped on the ground near the governor's building in Gao, the headquarters of the NMLA," Toure said by telephone around 30 minutes after the fighting had stopped. "In all the buildings that the NMLA had controlled, their flag had been taken down and been replaced by the flag of the Islamists."
The switch in rebel control of the buildings of Gao was confirmed by a second resident, Mohamed Diamoye, a doctor at the local hospital who said three bodies had been brought to the morgue. They included that of a MUJAO fighter.
A member of the NMLA, who requested anonymity because of the sensitivity of the matter, said that one of the group's leaders was accidentally shot during the clash. Bilal Ag Cherif, the NMLA's secretary general, was airlifted to Ouagadougou, the capital of neighbouring Burkina Faso, in a helicopter.
Among the dead is Col. Bouna Ag Atouyoub, a colonel in the NMLA, said the group's Paris-based spokesman Moussa Ag Acharatoumane, who was reached by telephone.
Rebels from the Tuareg ethnic group seized control of the northern half of the nation of Mali in late March, taking advantage of the power vacuum created by a coup in Bamako, the capital. Leading the rebel advance was the NMLA, which said it was fighting to create an independent homeland for the Tuareg people in northern Mali, known as the Azawad in the Tamashek language.
It was not long before it became clear that the rebels were not united. At least two Islamist factions emerged, including MUJAO, which seized parts of Gao, and Ansar Dine, which based itself in Timbuktu. Both Islamist groups are believed to have links to al-Qaida and analysts say their open existence in northern Mali poses a grave security risk not just for Mali, but for the region.
Last month, the rebel factions met in Gao to try to hash out a common position, signing an accord that created a governing council. The talks disintegrated just weeks later over the issue of Shariah, with the Islamist faction wanting the strict Islamic law applied throughout northern Mali, a position that the secular NMLA rejects.
A fighter with the NMLA who requested anonymity because of the sensitivity of the matter said that a convoy of NMLA soldiers had left the northern city of Kidal headed toward Gao to try take back the town. A military official with the NMLA, however, downplayed the attack, saying that the buildings seized by MUJAO in Gao were not strategically important.
"I cannot confirm that the HQ of the NMLA, which is located inside the governor's building in Gao, has been taken by the Islamists from MUJAO," said Col. Asaleth Ag Khabi, the deputy to the chief of staff of the NMLA and the head of military operations in Gao.
"But in any case this headquarters is just a political office. Not a military building. We are dealing with Islamists that are from Gao, that are here from a long time ago. Who were born and raised here. And this combat is not over yet," he said by telephone from an undisclosed location in northern Mali.
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