Nigeria's security services have hailed the arrest of the leader of the Boko Haram splinter group Ansaru, Khalid al-Barnawi, saying it will lead to them to other senior Islamist commanders, AFP reports.

"The arrest of Barnawi is a huge success and will have a profound effect on counter-terrorism operations in Nigeria and beyond," one security source told AFP.

"He is a known transnational terrorist and the backbone of all Al-Qaeda affiliate groups in West Africa."

Barnawi, designated a global terrorist by the United States since 2012, was detained on April 1 with three others in the Kogi state capital, Lokoja, and found with four Thuraya satellite phones.

The phones "provided several leads" to "high-profile Boko Haram and Ansaru elements" in the capital, Abuja, Lokoja and the central city of Jos, said another source.

"This has been our biggest breakthrough against terrorism in Nigeria ever," said a third.

Barnawi is certainly a major prize for Nigerian intelligence, the Department of State Services (DSS), which called him "a trained terrorist commander" who also recruited for Al-Qaeda affiliates.

He is accused of masterminding a string of kidnappings of Westerners between 2011 and 2013.

Boko Haram has been pegged back by an aggressive fightback from the Nigerian military since January last year, losing territory and its capacity to mount conventional attacks.

President Muhammadu Buhari has gone so far as to say the militants were "technically" defeated, even if suicide and bomb attacks have continued in northeast Nigeria, Cameroon and Niger.