An armed group has released former Libyan premier Ali Zeidan, nine days after he was kidnapped in Tripoli while making his first visit home for three years, a family member and friend said Wednesday.

Zeidan, 67, who served as premier from November 2012 to March 2014, was snatched on August 13 from his hotel.

He was on his first visit to Tripoli since leaving the country following his ouster by parliament on charges of embezzling public funds.

"Mr Zeidan was released on Tuesday night. He is in very good health and should be leaving Libya" on Wednesday, said Karam Khaled, a close friend.

He declined to give details on the release but has blamed a militia loyal to Libya's UN-backed Government for National Accord (GNA) for the kidnapping.

Zeidan Zeidan, a son of the former premier, said they had spoken several times on the telephone since his release.

"For the time being, we have no details on the circumstances of his detention," he told AFP. "But the most important thing is that he's very well and was not mistreated."

Zeidan returned to Libya in early August for the first time since his dismissal and was planning a Tripoli press conference to respond to the embezzlement charges, according to Khaled, who accompanied him.

He said the former prime minister's visit had been coordinated with Fayez al-Sarraj, the current premier in the GNA.

"It was the GNA that prepared the visit, including protocol at the airport and the hotel reservation," Khaled said, adding that an armed group's initial attempt to seize Zeidan on August 12 had been foiled by hotel guards.

In October 2013, gunmen seized then premier Zeidan from another hotel in the capital but he was released after several hours.

Since a 2011 revolution that ousted longtime dictator Moamer Kadhafi, Libya has been plagued by security problems and political actors have had to depend on rival militias battling for control of the country.