Libyan militias captured Muammar Gaddafi's chief spokesman on Saturday, the government said, but an audio clip posted on Facebook purporting to be the voice of Moussa Ibrahim denied his capture.
There was no independent verification of the authenticity or timing of the Facebook post, dated Oct. 20, a year to the day after the dictator's death.
A statement from the prime minister's office said Ibrahim, who was the mouthpiece of the Gaddafi regime during last year's war, was caught in the town of Tarhouna, 70 km (40 miles) south of Tripoli.
"He is being transferred to Tripoli to begin interrogation," the statement said.
The government has previously made false claims regarding the capture of Gaddafi loyalists, and produced no photographs on Saturday showing Ibrahim in detention.
His whereabouts have been unknown since the fall of the capital in August 2011. The government claimed to have caught him last October but he called Reuters to deny the report.
Libya's new rulers have led the nation to elections but have struggled to impose their authority on a country awash with weapons. Leader Mohammed Magarief said some areas of the country still needed to be fully "liberated".
In the Facebook clip, a voice sounding like Ibrahim's said: "I am addressing you a year after the martyrdom of the great leader and his free companions and the fall of the legitimate free nation of Libya under NATO's bombings and their criminal allies.
"About the news of my arrest ... and the spreading of this news in the media, this is just to divert attention from the crimes that are being committed by NATO allies."
The voice on the recording said Ibrahim, who held regular press conferences in the luxury Tripoli hotel were journalists stayed during last year's war, was no longer in Libya.
Former rebel fighters have maintained Gaddafi loyalists have used the town of Bani Walid, some 160 km (100 miles) south of Tripoli, as a safe haven, protected by the large Warfala tribe which has historically been loyal to Gaddafi's tribe.
Speaking on television late on Friday about the insecurity still plaguing parts of Libya, national congress leader Magarief singled out Bani Walid which has seen deadly clashes in the last few days as the army struggles to impose order.
"The campaign to liberate the country has not been fully completed," Magarief said.
He cited "delays" in the formation of the army and police and the failure to disarm and integrate former rebels.
"This lack of care has led to the spread of chaos that has lured the old regime to infiltrate the country's institutions inside and to conspire with the regime loyalists on the outside," Magarief said.
"And the chaos has lured others to kidnappings, stealing, and to create non-legitimate prisons. What has happened in Bani Walid in the last few days falls under this...it has become a safe haven for a large number of those who are outside of the law."
Militias, aligned with the Defence Ministry, have shelled the hilltop town of 70,000 for several days. A spokesman for the Bani Walid militia Colonel Salem al-Wa'er said fighting continued again on Saturday.
The Libyan state news agency LANA said the number of deaths in the clashes reached 14, with 200 people injured.
Many of the militia members are from the rival town of Misrata, which was enraged by the death of rebel fighter Omran Shaban after two months in detention in Bani Walid.
Shaban, from Misrata, was the man who found Gaddafi hiding in a drain pipe in Sirte on Oct. 20, 2011.
Libya's congress ordered the Defence and Interior Ministries to find those responsible for abducting Shaban and suspected of torturing him to death. It gave Bani Walid a deadline to hand them over. The army chief of staff said on Thursday the army was heading to the town to try and restore order.
"This is not targeting a region, a tribe, or unarmed civilians but outlawed men," Magarief said.
Tensions between Misrata and Bani Walid underscore the challenge Libya's new rulers face in reconciling groups with long-running grievances.
While Misrata spent weeks under siege by Gaddafi forces in last year's war, Bani Walid was one of the towns that remained loyal to Gaddafi longest.
It remains isolated from the rest of Libya and former rebels say it still harbours pockets of support for the old government.