Boko Haram's leader said in a video obtained by AFP on Thursday that the group was behind a daring raid on military installations in the north Nigerian city of Maiduguri earlier this month.
"Allah the Almighty has given us victory in the attack we launched inside Maiduguri (which was) called Borno in ancient times," said Abubakar Shekau in a 40-minute clip.
Speaking in Arabic, Hausa and Kanuri widely spoken in northeast Nigeria, Shekau added: "We stormed the city and fought them (and) Allah blessed us with lots of booty," he said.
The video, which was obtained through an intermediary, shows Shekau dressed in military fatigues with a turban and Kalashnikov assault rifle leaning on his chest.
He speaks for 19 minutes in all while the rest of the tape shows images of burning buildings and aircraft said to be from the December 2 attack in Maiduguri, which is capital of Borno state.
It also shows a display of weapons the banned Islamist group says it seized in the attack, including dozens of Kalashnikovs and rockets.
The authenticity of the tape could not be verified independently.
Gunmen who arrived on pick-up trucks besieged an army and air force base, destroying aircraft, razing buildings and setting shops and petrol stations ablaze, witnesses said.
The early morning raid was seen as significant because the Nigerian military had previously claimed to have pushed the militants out of urban centres and into more remote, rural areas.