What you need to know:
- Residents in the city confirm the Islamist fighters seemed to have moved outside city lines and that their radio station, Radio Andalus, was off the air.
Al-Qaeda linked al-Shabaab rebels said on Saturday that they have abandoned the southern Somali port city of Kismayu, their last bastion in the country, a day after an assault by African Union troops.
"The military command of Shabaab mujahedeen ordered a tactical retreat at midnight," spokesman Ali Mohamud Rage told AFP.
The announcement came a day after an assault on the city by African Union troops, who had been trying to dislodge the insurgents from the key coastal city for days.
Residents in the city confirmed that the Islamist fighters seemed to have moved outside city lines and that their radio station, Radio Andalus, was off the air.
"We don't know where they went to... but early this morning the last military vehicle left the town," said Hassan Ali, a resident.
"Even their radio station is off air," he added.
Al-Shabaab fighters on the ground also confirmed the withdrawal.
"We got orders from our superiors to withdraw from the city... this is part of broader military tactic we have set for the enemy," said Sheikh Mohamed Abu-Fatma, a Shabaab commander, told AFP by telephone.
Kismayu has been a vital lifeline for the Shabaab since the African Union force in Somalia (AMISOM) force re-conquered most of Mogadishu last year and Ethiopian troops stripped them of other key cities in the east.
Observers have consistently said that the loss of Kismayu would leave the Shabaab, who once controlled 80 percent of the country, unable to retain large swathes of territory.
But in places where the Shabaab have abandoned fixed positions, most notably in the capital Mogadishu, they have switched to guerrilla tactics and remained a threat.