Somali troops backed by African Union forces have launched an assault to retake the al-Shabab stronghold of Barawe, key to the financing of al-Shabab fighters.

Al Jazeera's Catherine Soi, embedded with the African Union Mission in Somalia (AMISOM) in Barawe, said "some al-Shabab fighters were fleeing the battle, taking boats and heading out to sea, while others were melting in to civilian areas."

Brigadier General Dick Olum, from AMISOM told Al Jazeera on Sunday that Barawe "was hours away from being taken".

"Barawe has one the biggest ports in Somalia, and taking the town will be a huge boost for the Somali government and AMISOM forces."