Kismayo — The Somali insurgent faction Al Shabaab has seized control of the southern port of Kismayo, after hours of fighting with Hizbul Islam rebels, Radio Garowe reports.

Heavy fighting erupted in Kismayo around 7am local time on Thursday morning, after Al Shabaab fighters attacked Hizbul Islam positions in Kismayo's northern neighborhoods.

At least 30 people have been killed in more than five hours of fighting, including 10 civilians who died after their fleeing vehicle overturned in the outskirts of Kismayo, local sources reported.

Kismayo medical sources said 70 wounded persons were admitted since the fighting erupted, with the city's main hospital reportedly overcrowded.

Senior commanders of Al Shabaab and Hizbul Islam were killed during the fighting, including the commander of Anole fighters, a man named Ali Said.

Anole is one of four factions that merged to form Hizbul Islam in Feb. 2009.

Inside sources said Al Shabaab's top commander for the Jubba regions, where Kismayo is located, died during the heavy fighting. The commander was named Aden Dhagoweyne, according to local reports.

Al Shabaab spokesman Sheikh Ali "Dheere" Mohamud told reporters in Mogadishu via a telephone press conference that Al Shabaab is not at war with Hizbul Islam.

"This war is not among the Mujahideen," said Sheikh Ali Dheere, adding: "Sheikh Ahmed Madobe [alone] is responsible for the war."

Sheikh Ahmed Madobe, a senior commander of Ras Kamboni Brigade, also part of Hizbul Islam, led Hizbul Islam fighters into Kismayo earlier this week to challenge Al Shabaab's unilateral rule.

In Mogadishu, Hizbul Islam spokesman Sheikh Ismail Haji Addow urged Al Shabaab to "stop the war" and said Hizbul Islam fighters were "defending themselves."

As of Thursday night, uneasy calm returned to Kismayo after Hizbul Islam fighters withdrew from the port town. Heavily-armed Al Shabaab guerrillas were reportedly patrolling Kismayo's five neighborhoods.