Boko Haram HQ destroyed - Nigeria
Nigeria's military claims to have destroyed the headquarters of Boko Haram in a north-eastern town.
The official Twitter account of the Nigerian Defence Headquarters announced: "FLASH: Troops this morning captured Gwoza destroying the Headquarters of the Terrorists self-styled Caliphate."
It followed with: "Several terrorists died while many are captured. Mopping up of entire Gwoza and her suburbs is ongoing."
It was not possible to verify the claimed victory which comes the day before presidential elections.
There was no mention of the Sambisa Forest, in the Gwoza local government area, where Nigeria's home-grown Islamic extremist group is believed to have camps. Warplanes have been bombarding the area for weeks.
Sambisa Forest is where extremists first took nearly 300 schoolgirls kidnapped in Chibok nearly a year ago. Some 219 remain missing.
The failure of the government and military of President Goodluck Jonathan to rescue the girls created international outrage and continues to dog Nigeria's leader as he stands for re-election.
Nigeria's military, with support of troops and military aircraft from neighbouring countries, in the past two months has retaken dozens of towns from Boko Haram. This comes after months of defeat at the hands of Boko Haram, with soldiers fleeing the battlefield after they ran out of ammunition.
Mr Jonathan's opponents have said the offensive is a political ploy, asking why Nigeria's military, of which he is the commander in chief, is suddenly capable of doing what it has failed to do for nearly six years.
Analysts attribute the success to newly acquired equipment including tanks, armoured cars and helicopter gunships, training by foreign instructors and a joint offensive with battle-hardened soldiers from neighbouring Chad, as well as troops from Niger and Cameroon.
A regional offensive against Boko Haram was mounted at the end of January amid growing international concern as the militants seized territory the size of Belgium, pledged to become the west Africa franchise of the Islamic State group operating in Syria and Iraq, and as the Nigerian insurgents spread their attacks across borders.
At least 10,000 people were killed in the Islamic uprising last year and more than 1.5 million people have been driven from the homes.
Nigeria's military also claimed to have driven Boko Haram from all three north-eastern states that had been an extremist stronghold.
Nigerian officials have said a multinational offensive aims to wipe out Boko Haram. Analysts and diplomats say that is overly optimistic and that they expect Boko Haram will be dislodged from territory but will be able to perform hit-and-run attacks and suicide bombings.
The military has been pursuing "a final onslaught" that has dislodged the insurgents from towns and communities in Adamawa, Yobe and Borno states, defence spokesman Major General Chris Olukolade told a news conference.
He added that several fighters were killed, many captured, and a "massive cordon and search" operation had been launched to hunt down fleeing insurgents and any hostages.
Defeated fighters are believed to be heading to the borders where troops from a multinational force are preparing to engage them, he said.
Boko Haram leader Abubakar Shekau declared Gwoza the capital of a new Islamic caliphate after he seized the town in August.