Syria fighting rages as world leaders meet

Fierce fighting has raged in key Syrian cities ahead of the UN General Assembly meeting.

Fierce fighting has raged in key Syrian cities ahead of the UN General Assembly meeting, with international peace envoy Lakhdar Brahimi saying he sees no end in sight to the brutal conflict.

Global Aid agency Save the Children said on Tuesday Syrian children are being "badly traumatised" after witnessing killings, torture and other atrocities, a day after at least 12 children were among 116 people reported killed nationwide.

Powerful explosions also rocked a military building in Damascus, causing casualties, the Syrian Observatory for Human Rights reported.

"The explosions were so powerful that the walls collapsed," Observatory director Rami Abdel Rahman told AFP of the headquarters on the Damascus airport road of the administration that manages schools for the children of martyred soldiers.

Regime forces again bombarded Aleppo in the north, focusing on the Hanano and Maysar districts in the east and Kalassa in the southwest, the Britain-based Observatory said.

It also said soldiers shot dead a young girl when they targeted the car she was in after midnight on the motorway linking the northern commercial hub to Damascus.

On Monday Brahimi, the UN and Arab League envoy, painted a grim picture of the Syrian crisis.

"There is no prospect for today or tomorrow to move forward," he told reporters after briefing the UN Security Council on his talks in mid-September with President Bashar al-Assad.

Reporting on his first visit to Syria since assuming his post, Brahimi said Assad "knows something must change" but he wants only a return to "the old Syria" which he and his father have ruled for more than 40 years.

Brahimi talked of food shortages, the "medieval" torture of detainees and damage to all but 200 of the country's 2200 schools.

The veteran troubleshooter, who took over from former UN secretary general Kofi Annan as Syria envoy on September 1, also appealed to the divided 15-nation Security Council for united backing.

The conflict has divided the Security Council, where Russia and China have already wielded their veto powers three times to resist international action.

Syria was set to be spotlighted again later on Tuesday when US President Barack Obama was expected to lead Western demands for action on the conflict, when the annual UN General Assembly begins.

Obama was to be one of the opening speakers at the gathering of world leaders where Syria, mounting fears of a military strike on Iran and anti-West protests in Muslim nations were set to dominate.

UN chief Ban Ki-moon, France's President Francois Hollande and Qatar's emir, Sheikh Hamad bin Khalifa al-Thani, a key backer of the Syrian opposition, were also expected to lambast Assad.

Ahead of the General Assembly, Egypt's President Mohamed Morsi told the US television channel PBS he opposes any foreign military intervention in Syria but believes Assad must go.

Since mid-July, the conflict has centred on Aleppo, where Free Syrian Army rebels say they control all of the axes around the northern metropolis and that their only real worry is attack from the air.

The FSA said one of its commanders, regime defector Colonel Kassem Saadeddine who is also a rebel spokesman, escaped an assassination attempt early on Tuesday.