US warns of links between Islamic State, Boko Haram

At "Ground Zero" in Africa's counter-terrorism fight, senior US officials warned of deepening links between the Islamic State and Boko Haram and prodded Chad's ruling strongman to introduce reforms for the sake of long-term stability.

But in a rare appearance before foreign journalists at his presidential palace, Chadian President Idriss Deby indicated he wouldn't help in the US-backed effort to install a unity government in Libya, his country's northern neighbour, a former foe and an incubator for Muslim extremist groups.

The visit to Chad by America's UN envoy, Samantha Power, and top US military officials such as Brig. Gen. Donald Bolduc, commander of special operations in Africa, highlights the country's precarious position dealing with a multitude of hostile militant groups and unstable neighboring governments.

It also underscores the impoverished, land-locked country's growing geopolitical value. Boko Haram has launched attacks on Chad's territory from its base in Nigeria to the southwest.

The Islamic State and al-Qaida in the Islamic Maghreb lurk in chaotic and lawless Libya to the north. To the east is Sudan's Darfur region; to the south is the Central African Republic, still recovering from years of interethnic conflict

The Boko Haram-IS nexus may pose the greatest immediate threat. Although Boko Haram pledged its allegiance to the Islamic State last year, the operational connection has been unclear.

Bolduc said the groups clearly share "tactics, techniques and procedures," from the way they conduct complex ambushes and set improvised explosive devices like roadside bombs, to how they undertake high-profile attacks on hotels.

Suggesting the relationship is expanding, he said Chad on April 7 intercepted a "large cache of different types of weapons" sent from Libya and intended for the Lake Chad region.

These included small arms, machine guns and rifles. "You can, I think, draw a conclusion," Bolduc told reporters.

The implication was that the weapons were sent by the Islamic State, which has established a foothold along Libya's Mediterranean coast, near the city of Sirte.