TRIPOLI - Tripoli's airport closed Saturday night after armed men in the vehicles of Libya's new national army tried to take control of of the installation from a powerful militia, according to reports.

It was the latest in a series of clashes between the rival militias which, in the absence of a fully-functioning central government, have wielded real power on the streets in Libya since a revolt forced out former leader Moammar Gadhafi.

Mukhtar Al-Akhdar, commander of the airport's security force and head of a militia unit from Zintan, south-west of Tripoli, which controls the international airport, told Reuters on Sunday that a convoy of vehicles approached a checkpoint about 3 km (2 miles) from the airport.

He said the armed men in the convoy said they had come to take over security, and a gunfight then broke out.

"No one was killed. We have only two people injured on our side," Al-Akhdar told Reuters. "These people were using national army vehicles. When we asked (acting army chief of staff Khalifa) Haftar about it, he said he did not know these people."

NTC military spokesman Ahmed Bani did not comment on the details of the incident but said: "There is no political or other problem. The problem is now sorted out."

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Hours earlier, Libya's president, Mustafa Abdul Jalil, begged for all sides to work for reconciliation, The Guardian reported.

Also Sunday, a team of U.S. weapons experts disposed of some 1,300 pounds (600 kilograms) of ordnance deep in the sand just outside Tripoli.

"Our goal is to help the Libyan people to secure these loose arms," said U.S. Assistant Secretary of State, Andrew Shapiro, who was on hand to watch along with the U.S. ambassador.

There have also been concerns following Libya's eight-month civil war about the massive amount of weapons and munitions that have gone missing, many of them taken from arms depots scattered about the country.

Shapiro said that since September, American experts have disabled around 5,000 shoulder-fired missile launchers — weapons that Western and Libyan officials have expressed concerns about because they pose a threat to civil aviation.

Separately, the head of the Libyan national army was ambushed at a checkpoint in the capital, the newspaper reported. The general's jeep escaped and two militiamen were later arrested, the Guardian quoted a spokesman as saying.

Power vacuum
Libya's central government is becoming slowly more assertive and signaling that it is time for the militias -- which emerged from the seven-month war to end Gaddafi's rule -- to hand over to the new national police and army.

Tripoli city council has given militias from other towns until December 20 to return home. The council chief said if they do not meet the deadline, all roads in the city will be blocked, except to defense and interior ministry vehicles.

Most militia leaders say publicly that they are ready to hand over to central institutions as soon as they receive the order to do so from the NTC.

But the national police and army are only just beginning to function. Some of the militias believe if they withdraw, that will leave a vacuum that will be filled by rival militias, in particular the powerful Islamists.

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Tripoli international airport has already been a flashpoint for tensions. Late last month, armed men from Zintan briefly detained Abdel Hakim Belhadj, the Islamist leader of one of Tripoli's most powerful militias, as he tried to catch a flight.

Reuters and the Associated Press contributed to this report.

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