Two Tunisian journalists who disappeared in Libya could still be alive, Tunisia's foreign minister said Tuesday, calling into question reports that they were killed by the Islamic State.

Journalists Sofiene Chourabi and Nadhir Ktari disappeared in Libya eight months ago. Libyan officials recently said captured militants said they were executed.

But speaking in front of Tunisia's parliament, Foreign Minister Taieb Baccouche said further proof is needed to confirm they are dead.

A Tunisian investigative judge is in Libya to try to determine their fate but has run into difficulties because the area where the journalists disappeared is under the control of the Islamic State.

"What is important for us is to discover the truth, whatever it may be," Baccouche said. "We have to be very careful, we are walking on eggs and dealing with many different parties."

The case has been closely followed in Tunisia. Before Chourabi became a journalist, he was a prominent activist during the 2011 revolution that overthrew Tunisia's dictator and kicked off the Arab Spring around the region.

The case has underlined the growing chaos in Libya, where power is shared by rival governments on either end of the country and hundreds of militias, as well as a powerful presence from the radical Islamic State group.

Despite the dangers, many Tunisians work in Libya and over the weekend, 172 were detained by authorities in Tripoli.

The Foreign Ministry has said they were picked up in an immigration sweep and would soon be released.

The Tunisian consul to Tripoli, Brahim Rezgui, however, said on Saturday that their arrest was in retaliation for the detention of a Libyan militia leader at the Tunis airport Thursday.

Authorities on Monday charged Walid Klib of the Libyan Dawn militia under the anti-terrorist law, judicial spokesman Sofiane Selliti said, without giving details.