The US-trained special forces, known as Danab were reported to have begun an operation aimed at wiping out Al-Shabaab from the entire areas located on the outskirts of Kismayo.
The local residents said the operation was carried out in Jamame, Kaban and Kamsume, key Al-Shabaab hideouts near the interim seat of Jubbaland regional administration.
Danab troops have arrested at least 20 people on suspicion of being Al-Shabaab members during the massive crackdown and taken to an undisclosed detention centre in the region.
The local army commanders say U.S. soldiers are involved in the operation targeting Al-Shabaab militants, in a bid to secure the areas around the southern port city of Kismayo.
Several bases belonging to Al-Shabaab have been destroyed during the joint operation by Somali and American troops, according to the commander of the 43rd battalion of SNA.