region] and leave them to their stones. We can never subdue them." The French therefore focused their intervention on the center and east of the country, leaving the Tibesti region largely alone. In 1969, Goukouni Oueddei, a Teda leader, and Hissène Habré, a Daza leader, emerged from the Tibesti to form the Second Liberation Army. In April 1974, the Second Liberation Army captured Bardaï from the Chadian government and took hostage the French archeologist Françoise Claustre, German doctor Christophe Staewen and Marc Combe, an assistant to Claustre's husband, and held them in the mountains. Staewen's wife and two soldiers of the Chadian army were killed. The West German government quickly paid the ransom and Staewen was released. The French government sent the military officer Pierre Galopin to negotiate with the rebels, but he was captured by the rebels and executed in April 1975. Marc Combe was able to escape in May 1975. The remaining hostages were released in January 1977 in Tripoli after France acceded to the rebel's ransom demand. The hostage incident, known as "L'affaire Claustre", caused a rift between the French and Chadian governments. Another rift formed between Goukouni and Habré, which by 1976 had spread to the Second Liberation Army, leaving one side commanded by Habré and the other commanded by Goukouni and supported by Libya. In June 1977, Goukouni's forces attacked the Chadian government stronghold in Bardaï. The rebels also attacked Zouar. These battles resulted in the death of 300 government troops. Bardaï surrendered to the rebels on July 4, while Zouar was evacuated. The Chadian government, led by Félix Malloum since Tombalbaye's overthrow in 1975, signed a peace agreement with Habré in 1978, although fighting with other rebel groups, many aligned with Libya, continued. Tibesti War In 1978, war broke out between Chad and Libya ostensibly over the Aouzou Strip, a borderland between Chad and Libya that extends into the Tibesti Mountains and is rumored to contain uranium deposits. In 1980, Libya used the strip as a base from which stage an attack, led by Goukouni, on the Chadian capital, N'Djamena, located in southern Chad and controlled by Habré. N'Djamena was toppled in December; however, under considerable international pressure, Libya withdrew from southern Chad in late 1981, and Habré's Armed Forces of the North (FAN) took control of the entirety of Chad with the exception of the Tibesti, where Goukouni retreated with his Libyan-backed Government