After two days of clashes, a military commander for the Sufi militia, Ahlu-Sunna Wal-Jamaa, says his forces have seized the town of Beledweyne in the Hiran region from Hizbul Islam rebels.
The commander, Aden Mohamoud, says both sides took heavy casualties in what residents describe as among the worst fighting there in recent months.
Mohamoud says Ahlu-Sunna forces are in full control of Beledweyne and the town is now calm.
The fighting broke out Sunday after Ahlu-Sunna fighters and local clan militias launched an offensive to capture Beledweyne, a strategic town near the border with Ethiopia.
The town changed hands several times in the past year between Hizbul Islam -- an Islamist group that was formed in early 2009 to oppose the Transitional Federal Government in Mogadishu -- and government and pro-government forces. For the past several weeks, Beledweyne had been controlled by Hizbul Islam fighters.
Last week, Ahlu-Sunna Wal-Jamaa successfully fought off an attempt by the country's most powerful Islamist group, al-Qaida-linked al-Shabab, to capture the town of Dhusamareb in the neighboring Galgadud region. The capture of Beledweyne now gives the Sufi militia the ability to protect smaller towns in between Beledweyne and Dhusamareb from an al-Shabab advance from southern Somalia.
Moderate Sufis who make up Ahlu-Sunna Wal-Jamaa began a war against al-Shabab militants in late 2008 over sectarian differences. Ahlu-Sunna is nominally aligned with the Transitional Federal Government. But the group has expressed frustration with the lack of support given to them by the government in Mogadishu.
Last month, Ahlu-Sunna's leadership began implementing measures to create a semi-autonomous administration in the areas they control in central Somalia. But the move threatened al-Shabab's plans to create its own ultra-conservative Islamic administration in the central regions. Analysts believe the attack on Dhusamareb was an attempt by al-Shabab to prevent Ahlu-Sunna leaders from advancing their plan.
Meanwhile, al-Shabab reportedly clashed with Hizbul Islam factions Monday in the town of Dobley in the Lower Juba region, near the border with Kenya. A Hizbul Islam commander told journalists that dozens of al-Shabab fighters had been killed. But his claim could not be independently verified.
In September, Hizbul Islam and al-Shabab ended their alliance in the Juba regions following a power struggle over the port city of Kismayo. Two clan-based factions of Hizbul Islam declared war on al-Shabab and the two sides have repeatedly clashed over territory in recent months.
Somalia's Transitional Federal Government is backed by the United Nations and militarily supported by neighboring Ethiopia and 5,000 African Union peacekeepers. But the government has been unable to function beyond the small area it controls in Mogadishu.
Fierce fighting has broken out in two towns in southern and central Somalia among three Islamist groups vying for power in the country. With the U.N.-backed transitional government unable to exert any influence in most areas of the country, various Islamist groups and factions are trying to fill the power vacuum.