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Fierce fighting rages in northern Syrian city of Aleppo

On Wednesday Syrian troops pushed even farther into the key city of Aleppo where rebels are running short on much-needed supplies. NBC's Richard Engel reports.

Troops loyal to Syrian President Bashar al-Assad assaulted rebel strongholds in Aleppo on Wednesday in one of their biggest ground attacks since rebels seized chunks of the country's biggest city three weeks ago.

Assad must win the battle for Aleppo if he is to reassert his authority nationwide, although diverting military forces for an offensive to regain control there has already allowed rebels to seize large swathes of countryside in the north.

Aleppo, at the heart of Syria's failing economy, has taken a fearful pounding since the 17-month-old uprising against Assad finally took hold in a city that had stayed mostly aloof.

"We have retreated, get out of here," a lone rebel fighter yelled at Reuters journalists as they arrived in Aleppo's Salaheddine district. Nearby checkpoints that had been manned by rebel fighters for the last week had disappeared.

Satellite images show Syria's bombardment of Aleppo, Amnesty says

Syrian state television said government forces had pushed into Salaheddine, killing most of the rebels there, and had entered other parts of the city in a new offensive.

Everyday more wounded Syrian rebels are brought in to Turkey and treated in border hospitals run by Syrian doctors and volunteers.  Medical supplies are in short supply and the hospitals underequipped.  NBC's Ayman Mohyeldin reports. 

It said dozens of "terrorists" were killed in the central district of Bab al-Hadeed, close to Aleppo's ancient citadel, and Bab al-Nayrab in the southeast.

'Situation is desperate' at makeshift hospitals on Syrian-Turkish border

But a rebel spokesman in Salaheddine, the southern gateway to Aleppo, denied Assad's troops had taken full control. "Syrian forces are positioned on one side of Salaheddine but they haven't entered and clashes are continuing," Abu Mohammed said.

According to the BBC, Wassel Ayub, a commander from the rebel Free Syrian Army, told the AFP news agency by phone: "For an hour and a half the Free Syrian Army has staged a counter-attack and reclaimed three streets out of five seized by regime forces."

Another FSA commander, Abdel Jabbar al-Oqaidi, told AFP news agency via Skype, according to the BBC: "It is not true the regime army has seized control of the district. It is true that there is a barbaric and savage attack."

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People resisting the army of President Bashar al-Assad in northern Syria cope with loss and prepare for fighting.

One activist with the rebel Free Syrian Army, who asked not to be named, said insurgents had fallen back to the nearby neighborhood of Saif al-Dawla, which was now under fire from army tanks inside Salaheddine and from combat jets.

Reporting from Aleppo, Al Jazeera's correspondent Ahmed Zaidan said "a large number of people have been killed or injured in a fierce battle near Salaheddine in which advanced Russian tanks have been used by the government forces."

Also reporting from Aleppo, journalist Martin Chulov, of the U.K.'s Guardian newspaper tweeted Wednesday: "Spent afternoon in Salahedin [sic] #Aleppo. No regime troops inside. Battlelines have not shifted. Lots of shelling and helicopters."

Bodies recovered from destroyed home near Aleppo

The intensity of the conflict in Aleppo and elsewhere suggests that Assad remains determined to cling to power, with support from Iran and Russia, despite setbacks such as this week's defection of his newly installed prime minister.

The Syrian Observatory for Human Rights, a British-based opposition watchdog, said more than 60 people had been killed across Syria on Wednesday, including 15 civilians in Aleppo. It put Tuesday's death toll at more than 240 nationwide.

Struggle for survival
Satellite images released by Amnesty International, obtained from July 23 to Aug.  1, showed more than 600 craters, probably from artillery shelling, dotting Aleppo and its environs.

"Amnesty is concerned that the deployment of heavy weaponry in residential areas in and around Aleppo will lead to further human rights abuses and grave breaches of international law," the human rights group said, adding that both sides might be held criminally accountable for failing to protect civilians.

The military's assaults in Aleppo follow its successful drive to retake neighborhoods seized by rebels in Damascus after a July 18 bomb attack that killed four of Assad's closest aides, including his feared brother-in-law Assef Shawkat.

On Monday Assad suffered the embarrassment of seeing his prime minister, Riyad Hijab, defect after only two months in office. Hijab apparently fled to Jordan with his family.

Yet even such high-profile defections and outside diplomatic pressure seem unlikely to deflect Assad from what has become a bitter struggle for survival between mostly Sunni Muslim rebels and a ruling system dominated by the president's minority Alawite sect, an esoteric offshoot of Shiite Islam.

Jordan's King Abdullah said he believed Assad would stick to his guns. "He believes that he is in the right. I think that the regime feels that it has no alternative but to continue," the monarch told U.S. broadcaster CBS.

He said Assad might try to carve out an Alawite enclave if he could not control of all Syria, describing such a territorial breakup as the "worst-case scenario" for its neighbors.

"If Syria then implodes on itself that would create problems that would take us decades to come back from," Abdullah said.

Assad has little sympathy in Jordan or other Sunni-ruled Arab nations, but he can count on staunch support from Iran, whose Shiite leaders see Syria, along with Lebanon's Shiite Hezbollah movement, as a pillar of an "axis of resistance" against the United States and Israel.

Sarkozy urges action
Former French president Nicolas Sarkozy called on Wednesday for rapid international intervention in Syria, likening its conflict to the early days of war in Libya in which he mobilized NATO-led action that helped rebels oust Moammar Gadhafi.

Breaking a long silence since losing May's presidential election to Socialist Francois Hollande, Sarkozy said he had spoken at length to Syrian opposition leader Abdulbaset Sieda this week and they agreed on the need for foreign intervention in the uprising against Assad.

"They noted a total convergence in their views on the seriousness of the Syrian crisis as well as the need for rapid action by the international community to avoid massacres," said the statement signed by Sarkozy and Sieda, who is president of the Istanbul-based Syrian National Council.

In contrast with Libyan conflict, Western powers are wary of intervention in Syria due to Assad's alliances with Russia and Iran, and Syria's position at the heart of sectarian divisions that radiate across the Middle East.

Reuters contributed to this report.

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