July 31 (Bloomberg) -- Syria’s army has “purged” Aleppo’s Salaheddine district of armed groups and is pursuing others in several neighborhoods as it tries to regain control of the city, state television said.

Al Arabiya television and Al Jazeera, which had a news crew in the Salaheddine district, reported that the area was still under rebels’ control. An Al Jazeera correspondent in Aleppo, Omar Khashram, was injured by mortar fire and brought for treatment to Turkey, where he was reported in stable condition.

Troops loyal to President Bashar al-Assad have been battling rebels who seized several neighborhoods in Aleppo, Syria’s most populous city and its commercial hub, since last week. The army pounded the city with heavy artillery and helicopter gunships, opposition groups said.

An officer interviewed by the state-run TV channel said “mercenaries” from other countries, including Yemen, Saudi Arabia and Turkey, were helping the rebels in Aleppo.

Aleppo, with a population the U.S. Central Intelligence Agency estimates at 3 million, is shaping up as the biggest test yet of opposition fighters’ capabilities against Assad’s artillery and air power.

Motee al-Bateen, a member of the executive committee of the Syrian National Council, the main opposition group, said he couldn’t confirm whether Salaheddine was recaptured by the army.

“How much territory the opposition holds is not important,” he said by telephone from Istanbul yesterday. “What’s important is to engage the troops in cycles of attack and retreat to exhaust them.”

City Shelled

Al-Bateen said the army was using mortars, rocket launchers and tanks to shell areas and avoid engaging rebels in close combat.

International and regional efforts have failed to end the violence in Syria, which began in March 2011 and has left more than 19,000 people dead, including 5,000 government troops, according to the Syrian Observatory for Human Rights, an opposition group.

Syrian state forces killed 85 people yesterday, mainly in the capital, Damascus, and Aleppo, according to an e-mailed statement by the Local Coordination Committees, an opposition group.

Lieutenant General Babacar Gaye, head of the United Nations observer mission in Syria, said he is “deeply concerned” about the violence in Aleppo.

UN Attacked

Gaye said that on his first field visit, he went to Homs province July 29. The city of Rastan there was heavily damaged by “an intensive shelling campaign and fierce fighting,” he told a news conference in Damascus yesterday, according to remarks e-mailed by his office. “There were damaged tanks left on the side of the streets, public infrastructure, such as bridges, was destroyed and homes on the main roads inside the town were largely damaged.”

More than 12 UN armored vehicles were attacked and destroyed in Syria as violence spread throughout the country, UN Secretary-General Ban Ki-moon told reporters in New York yesterday.

“It is quite fortunate that nobody got injured by these attacks,” Ban said. “It was only because of these armored vehicles, which protected our mission.” The mission of UN unarmed observers is being dismantled after a cease-fire agreement failed to take hold.

Oppressive Acts

The U.K. Foreign Office said Syria’s charge d’affaires, Khaled al-Ayoubi, has left his post in the Syrian Embassy in London, saying he is unwilling to represent “a regime that has committed such violent and oppressive acts against its own people,” the Foreign Office said in an e-mailed statement yesterday. He was the most senior Syrian diplomat serving in London, it said.

About 200,000 people have fled Aleppo and nearby areas in the past two days, Valerie Amos, the UN’s top humanitarian affairs official, said in a statement July 29. The security situation in cities and along main transport routes is hindering humanitarian agencies’ efforts to reach displaced families, she said.

“It’s pretty clear that Aleppo is another tragic example of the kind of indiscriminate violence that the Assad regime has committed against its own people,” U.S. Defense Secretary Leon Panetta told reporters July 29 on his plane as he began a five- day Mideast trip. “If they continue this kind of tragic attack on their own people, it’ll ultimately be a nail in Assad’s coffin.”

Saudi officials and citizens donated almost 406 million riyals ($108 million) by the seventh day of the Saudi National Campaign to Support the Brothers in Syria, which was ordered by King Abdullah, state-run Saudi Press Agency said yesterday.

--With assistance from Kitty Donaldson in London, Zaid Sabah Abd Alhamid and Gopal Ratnam in Washington and Flavia Krause-Jackson in United Nations. Editors: Terry Atlas, Jim Rubin.