Clan sources said fighting broke out between the Marehan and Dir clans in the central Somali town of Herale and fighting was continuing with no ceasefire agreement on sight.
Other sources in the Marehan clan confirmed the fighting, but were unable to give the death toll.
Twenty-seven people were killed and 45 others wounded at the end of October when the two clans fought each other in Herale village of Abudwaaq district in Somalia's Galgudud region.
The clashes are said to have been triggered by animosities over the murder in April of a prominent Marehan elder by people believed to be Dir clansmen.
Somalia has been without a nationally recognised government and torn apart by factional warfare since the collapse of president Mohammed Siad Barre's regime in 1991.
A reconciliation conference aimed at restoring a national administration in the Horn of Africa country has been going on in neighbouring Kenya since October last year.