Military sources said six people were killed when a group of Guinean soldiers attempted to seize control of a military airbase near the capital, Bissau.

The fighting went on for about two hours early Sunday before the mutineers were defeated by military loyal to the Chief of General Staff of the Armed Forces, Antonio Indjai, said an army officer who spoke at the military headquarters on condition of anonymity. There is no indication if any senior officers were involved in the uprising.

The apparent attempted coup was against the military junta that itself seized power in April.

Guinea-Bissau was just weeks away from holding a presidential runoff election when soldiers attacked the front-runner's home and arrested him along with the country's interim president on April 12. No leader in nearly 40 years of independence has finished his time in office in Guinea-Bissau, a former Portuguese colony on Africa's western coast that has long been plagued by coups.

Following the April coup, military leaders agreed with 26 fringe parties to establish a National Transitional Council to rule the country for two years.

But ECOWAS — the Economic Community of West African States of 15 neighboring states — rejected that agreement and instead demanded a 12-month transition that would include the coup leaders in key positions and culminate in a presidential election. ECOWAS leaders also authorized the deployment of a 600-strong standby force.

United Nations Secretary General Bank Ki-moon told the General Assembly in May that he was concerned about reports of human rights violations by the military junta.

"Let me speak clearly: those responsible for the coup and subsequent violations of human rights will be held accountable by the international community," he said.