By Hamid Ould Ahmed
ALGIERS (Reuters) - A French judge is visiting Algeria as part of an investigation into the killing of seven French Trappist monks during Islamist-linked violence 18 years ago, an Algerian justice official said on Tuesday.
Judge Marc Trevidic arrived on Sunday and will attend the exhumation of the monks' remains at the Tibehirine monastery, 80 km (50 miles) south of Algiers, where they were killed in 1996, the official said. Only their severed heads were recovered and the circumstances in which they died are unclear.
"An Algerian judge will travel to France to complete the investigation," one judicial official told Reuters, asking not to be named because he was not authorised to talk to the media.
About 200,000 people were killed in Algeria during more than a decade of violence that erupted in the early 1990s between Islamist militants and security forces. The conflict was marked by massacres and the killing of civilians. Some of the murders remain unresolved.
Algerian authorities say the monks were abducted by militants and found dead with their throats cut two months later but that version has been questioned by several sources and France opened an official inquiry into the incident in 2004.
The monks' murder had been claimed by the Islamic Armed Group (GIA), a militant group known at the time for targeting foreigners in the former French colony.
"What the two judges will do is part of a judicial cooperation agreement that the two countries signed (in 2005) to fight against terrorism and organized crime," the official said.
Algeria and its former colonial ruler are also cooperating over last month's kidnapping and beheading of French tourist Herve Gourdel who was captured while hiking in mountains east of Algiers by militants allied to Islamic State extremists.
The Caliphate Soldiers group claimed to have captured and executed Gourdel to punish France for its military operations against Islamic State, which has taken over large parts of Syria and Iraq.
(Editing by Patrick Markey and Janet Lawrence)