UN expert held in Tunisia over 'espionage' freed on bail: sources

Moncef Kartas is a member of the UN panel of experts investigating allegations of violations of an arms embargo and other sanctions imposed on Libya.

The Tunisian-German dual national was detained on arrival in Tunis on March 26.

"The indictment division has decided to release Moncef Kartas on bail," prosecution spokesman Sofiene Sliti said.

But Kartas was still being prosecuted for the "unofficial collection of information related to terrorism, which constitutes a dangerous crime", he told AFP.

The investigation had uncovered equipment used to control civil and military air traffic and whose use "requires authorisation", he added.

The United Nations said it was "encouraged" by his release.

"We have been informed that earlier today a Tunisian appeals court has reviewed the case against Mr Kartas and has decided to release him," spokesman Stephane Dujarric told reporters at UN headquarters in New York.

"We are currently seeking further information from the government including with respect to the status of the legal proceedings against Mr Kartas."

Kartas's defence team has said the charges are linked to the arms expert's possession of a device allowing him to have access to data on flights of civil and commercial aircraft.

The device, an RTL-SDR, was used "only for monitoring air traffic to Libya, in order to identify flights that could be linked to violations of the arms embargo", said his lawyer, Sarah Zaafrani.

Last week, the United Nations rejected Tunisia's reasons for Kartas's arrest and demanded charges be dropped and his immediate release.

It argued that, as a UN employee, Kartas was subject to diplomatic immunity, but Tunisia challenged this.

The UN panel investigating the alleged sanctions breaches has reported that arms and ammunition deliveries still reach warring parties in Libya - with the involvement of member states - despite the embargo.

German Foreign Ministry spokesman, Rainer Breul said German officials raised the detention of Kartas with Tunisia's ambassador last month and sent several diplomatic notes directly to Tunis.

It came after a group of researchers published an open letter in several European newspapers, demanding his immediate release.

"The detention of Moncef Kartas on false grounds and in violation of his immunity raises serious questions about the rule of law in Tunisia," wrote the group of around a hundred academics and researchers.

They said that "not a single piece of evidence" had been released to justify his detention.

Libya, which borders Tunisia, has seen an uptick in violence since military strongman Khalifa Haftar launched an offensive on April 4 to take the capital Tripoli from the UN-recognised government.

An arms embargo has been in force since Libya's 2011 revolt that toppled its longtime ruler Muammar Qaddafi.

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