Al-Qaeda has named a militant Islamist commander - trained in Afghanistan and known for his ruthlessness - as its key representative in Mogadishu, as clashes between government troops and insurgents broke out in the Somali capital for the second day.

In this morning’s exchanges, which took place in both northern and southern parts of the city, insurgents fired rocket-propelled grenades, mortars and heavy machine-guns as government troops responded with a barrage of artillery and machine-gun fire, according to witnesses.

No casualties were yet reported, but terrified residents - unwittingly caught up in the exchanges - rushed to make their way out of Mogadishu amid fears that the latest bloodshed would spread.

Today’s events came a day after fierce fighting between government forces and insurgents killed at least 14 people, including soldiers whose bodies were dragged though the streets and set on fire.

The violence – some of the worst in the Somali capital since last year’s ousting of Islamists – led Prime Minister Ali Mohamed Gedi to urge civilians to leave areas in southern Mogadishu “for security reasons”.

As they fled the city, residents spoke of how they feared fighting was set to escalate. “All the fighting sides are making warlike statements and are preparing for war,” said Amina Sabriye, a mother of six, as she fled from Shirkole neighbourhood. “I have never seen a mass exodus on this scale in recent years,” added 86-year-old Mohamed Mukhtar Sadiq.

Fears of a step-up in violence were further fuelled as the Somali Government claimed that al-Qaeda had named an Islamist commander, Aden Hashi Ayro, as its leader in Mogadishu, raising the unwelcome possibility of a broader insurgency, involving foreign Islamic extremists linked to Osama bin Laden’s terror network.

“After Somali terrorists made consultations with al-Qaeda, Ayro was named as chief of al-Qaeda in Mogadishu,” Salad Ali Jelle, Deputy Defence Minister, told a press conference in Mogadishu. “They (Islamists) are killing people and intellectuals who are supporting the government.”

Mr Jelle said that Ayro was leading insurgents in recent fighting in Mogadishu, which has seen a dramatic escalation since government forces – backed by Ethiopian troops – drove out the Union of Islamic Courts (UIC) last December. “The government strongholds were attacked by the remnants of the Islamic courts led by Aden Hashi Ayro,” he said.

Western intelligence officials have long claimed that there are numerous al-Qaeda operatives taking refuge with Somali Islamists – a charge denied by the Islamists themselves.

Rob Crilly, recently in Somalia for The Times, said that Ayro was a known figure to US authorities, having been a key military commander on the ground under the regime of the Islamic courts.

“He is known for being a nasty piece of work - probably at the helm of a group of young thugs who are loyal to him - and is seen as being at the forefront of elements involved in creating unrest in Mogadishu,” said Crilly. “He is thought to be close to Sheikh Aweys, who is thought to have been the mastermind behind the Islamic courts coming to power, serving as the tactical power while Ayro himself was working on the ground.”

He added that Ayro was one of the targets of US air strikes in Somalia in January, aimed at driving out suspected al-Qaeda operatives hiding in the country. “The strikes did not get him, and the feeling is that while he fled from Mogadishu to the south of the country after the Islamists were ousted, he may well have returned to the capital and be there now.

“Although he is not necessarily the leader of al-Qaeda in Mogadishu, he is a key element. The situation in Somalia is very complex – there is no one leader as such, but rather various elements all stirring unrest. As well as the Islamists, there are warlords and criminal gangs, out to exploit the violence for their own gains.”

Earlier this month, an Islamist website released an audio-taped message attributed to Ayro, which called on Somalis to attack and kill Ethiopian troops deployed in the country.

Western intelligence sources have warned that Somalia risks becoming a terrorist haven if efforts to empower the government fail in the face of fierce opposition from powerful clans. Some 1,500 Ugandan troops are now in Somalia as part of a proposed 8,000-strong African Union force aiming to help government troops regain control and Ethiopian forces to leave.

In today’s scenes, witnesses reported hundreds of government troops being deployed to reinforce forces fighting against insurgents in areas in the north of the capital – which had previously been relatively calm. In a southern Mogadishu, others reported gunmen attacking government and Ethiopian troops based at the former defence ministry building, echoing yesterday's scenes.

“The fighting in Mogadishu will not stop until we defeat them (the insurgents),” Mr Jelle insisted. “We will pursue our aim of stabilising Mogadishu. This plan will not be hampered by a few individuals."

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