Mogadishu - Fresh clashes between government forces and Islamist insurgents broke out in the Somali capital Mogadishu Wednesday as the worst fighting in months showed no sign of ending.

Witnesses said that shelling and gunfire could be heard in the north of the city as insurgent group al-Shabaab exchanged fire with pro-government forces.

There was no indication of new casualties in the latest round of a battle that has gone on for almost a week, killing over 120 people, injuring hundreds and sending tens of thousands fleeing.

Insurgent groups al-Shabaab and Hizbul Islam claim they have gained ground from the Islamic Courts Union (ICU), a militia that is now supporting the new moderate Islamic regime, during the fighting.

The groups say that President Sheikh Sharif Sheikh Ahmed and his government, which controls only parts of Mogadishu, is too close to the West.

Sheikh Sharif, who led the ICU when it controlled Mogadishu in 2006 and worked alongside many of those who are now insurgents, came to power earlier this year as part of a Western-backed peace process.

The insurgency has claimed the lives of around 16,000 people, mainly civilians, since early 2007, and the resultant insecurity has helped feed an explosion of piracy in the Gulf of Aden.

Somali civilians are also struggling with a drought that Marc Bowden, the United Nations' top aid official for the Horn of Africa nation, said Tuesday is the worst in a decade.

Bowden said the drought has left almost half of the nation malnourished and that 3.2 million people are in urgent need of food aid.

Somalia has been embroiled in chaos since the 1991 ouster of dictator Mohamed Siad Barre, and is widely regarded as a failed state. (dpa)