Libyans turned over hundreds of weapons at collection points in the capital and the eastern city of Benghazi on Saturday following rallies which called for disarmament and the disbanding of militias.
A steady stream of men surrendered their weapons to national army troops stationed in Tripoli's Martyrs Square and in Benghazi's Freedom Square, AFP journalists reported.
"This is the first drive and it won't be the last," army spokesman Ali al-Sheikhi told AFP in reference to the campaign launched by the army in partnership with civil society organisations.
Colonel Hussein Abdullah Khalifa, overseeing the collection of weapons in Tripoli, said the initiative was galvanised by anti-militia rallies pressing for a united army which were held in Libya's two largest cities this month.
"We are astonished by the positive turn out," he said.
Tripoli campaign organiser Ziad Hadia told AFP that hundreds of people turned in "light, medium and heavy weapons as well as vast amounts of ammunition ranging from bullets to tank shells."
Most people handed in assault rifles, he said.
"We also received six heat-seeking missiles," added Hadia, while one person had come forward with a tank which is to be delivered to the army later at an undisclosed location.
In Benghazi, the army tallied some 730 light weapons, 200 hand grenades, 100 anti-personnel and anti-tank mines, along with 20 000 assorted ammunition, an AFP journalist said.
Those numbers represent just a fraction of the arms that spilled out of the arsenals of toppled dictator Moamer Kadhafi but it was seen as a step forward in a country where many cling to their weapons citing insecurity.
"To achieve security we must take the first step ourselves," said Mustafa Abu Hmeid, a 23-year-old mechanic clutching a rifle, a treasured spoil of the 2011 conflict which ended in Kadhafi's ouster and death.
Housewife Mariam Abu Swera expressed relief: "As long as there are arms on the streets, I can't move freely or go about my normal life, so we really welcome this step."
The day-long collection drive was spearheaded by the national army and private television station Al-Hurra, which drummed up support through its live broadcasts from Tripoli and Benghazi.
Its success pushed organisers to extend the deadline to 10 pm (2000 GMT).
Organisers in both cities will raffle off prizes, including two cars, at the end of the collection. They said the process would be repeated to include other cities.
A September 11 attack on the US consulate in Benghazi that killed four Americans, including the US ambassador, was followed by mass anti-militia protests in the city, increasing pressure on Libyan authorities to tackle insecurity.
On Friday, hundreds of people rallied in Tripoli in support of a national army and against armed groups.