(AP) BEIRUT - The U.N.'s new envoy to Syria said on Saturday that President Bashar Assad's regime should realize that the need for change was both "urgent" and "necessary" and that it must meet the "legitimate" demands of the Syrian people.
Lakhdar Brahimi's comments in an interview with al-Arabiya television came as Syrian warplanes and ground forces pounded the country's largest city, Aleppo, with bombs and mortar rounds while soldiers clashed with rebels in the narrow streets of its old quarter, according to activists.
The latest violence shows that government troops are still struggling to regain full control of the city from the lightly-armed rebels nearly five weeks after they stormed their way into it in a surprise offensive. Activists said rebels also captured an air defense facility in the east of the country near the border with Iraq.
"The Syrian government realizes more than me the extent of the suffering endured by the Syrian people," Brahimi told al-Arabia on his first day as the new U.N. envoy in Syria, replacing Kofi Annan who quit after his six-point plan including an April 12 cease-fire failed to stop the bloodshed.
Speaking in New York, he said: "The need for change is urgent and necessary. The Syrian people must be satisfied and their legitimate demands are met." A former Algerian foreign minister and a seasoned international trouble shooter, Brahimi said he enjoyed the "full and clear" support of the U.N. Security Council.
He also called for an end to the violence but acknowledged that he does not have a set of preconceived ideas on how to resolve the Syrian conflict. "We will try to overcome the obstacles that Kofi Annan faced," he added.
The Syrian conflict has its roots in mostly peaceful street protests that started in March last year. It has since morphed into a civil war, with at least 20,000 people killed so far, according to rights activists.
The Britain-based Syrian Observatory for Human Rights said the clashes in Aleppo were concentrated in several tense neighborhoods -- Hanano, Bustan al-Qasr, Sukkari and Maysar. It reported injuries and damage to buildings.
Another activist group, the Local Coordination Committees, said the government was making heavy use of warplanes in attacking rebel areas.
An Associated Press Television video showed rebel fighters, some in civilian clothes, in the street trading fire with government troops.
Activists say that this is the second day of a rebel push in Aleppo dubbed "Northern Volcano" targeting security facilities in the city and the surrounding province, including an artillery training school, a compound of the feared air force intelligence, and a large army checkpoint.
For over a year after the uprising against Assad's rule began nearly 18 months ago, Aleppo and Damascus stayed relatively quiet. But in July, rebels launched a brazen attack on the two cities, capturing several neighborhoods.
Government forces have regained most of the Damascus area but are being held at bay in Aleppo.
In the east, the Observatory reported that rebels captured an air defense post in the town of al-Boukamal in the oil-rich province of Deir el-Zour that borders Iraq. The opposition has claimed advances in the area in recent days.
A video released by activists showed soldiers who said they were captured at the post after rebels took it. The authenticity of the video could not be independently confirmed.
Despite the government's control of Damascus, opposition fighters continue to stage attacks using hit-and-run tactics in neighborhoods where they enjoy popular support, activists say.
Early Saturday, government forces bombarded the capital's southern neighborhood of Tadamon followed street fighting with rebels there, the Observatory said. The LCC said troops also shelled the nearby neighborhood of Hajar Aswad.
The state-run news agency SANA said army Brig. Gen. Taher Subeira, was killed by "terrorist" who placed a bomb under his car while parked in front of his Damascus home and detonated it when he got into the vehicle.
The Observatory said the bodies of five unidentified people were found in the neighborhood of Qadam, all shot execution-style.
Other clashes were reported in Idlib province on the border with Turkey, in Daraa near the Jordanian frontier, and in the central province of Homs near Lebanon, activists said.
SANA meanwhile reported Saturday that 225 detainees who took part in anti-government protests were released. The amnesty by authorities is the second in a week. On Monday, some 378 prisoners from Damascus and the central province of Homs were freed.
Rights activists say tens of thousands of Syrians have been detained over the past 18 months.