The fierce fighting between fighters loyal to al-Shabab and their archrivals Ahlu Sunnah began in the Rage Ele area in Middle Shabelle on Saturday night and continued Sunday, a Press TV correspondent reported.
"We attacked the area and overpowered al-Shabab fighters," Ahlu Sunnah spokesman Sheikh Muse Huseein said.
The government of President Sheikh Sharif Ahmed has recently brought Ahlu Sunnah on board ahead of an expected military push against the militants.
No civilian casualties have been reported but eyewitnesses say with the scale of fighting, casualties are expected to rise on both sides.
Meanwhile, clashes also broke out in the Gal-qoryale area that connects Elbur, al-Shabab's largest military base, and Guriel town, Ahlu Sunnah's stronghold in the central Galgadud region.
Residents say Al-Shabab attacked the area, driving the local fighters away.
The clashes come as hundreds of al-Shabab fighters have reportedly been deployed in the region ahead of a planned offensive against Ahlu Sunnah, which controls large swathes of central Somalia.
Al-Shabab is fighting against the Somali government and African Union troops.
Somalia has not had a functioning government since warlords toppled Siad Barre in 1991.
The vacuum of power opened a Pandora's Box of chaos and violence as warlords and their militias fought for power for years.
The Union of Islamic Courts created a semblance of peace and order in southern Somalia for about six months in 2006, but the Ethiopian invasion of December 2006 ended the brief lull in the storm in southern Somalia.