ALEPPO, Syria -- The United States and Russia were to begin talks this week on the fighting in Aleppo, Syria, as Russia’s foreign minister said he expected a deal to withdraw rebel forces from the city.

Meanwhile, CBS News correspondent Debora Patta reports, the government campaign to take back the besieged city was intensifying.

Civilians fled a barrage of artillery and airstrikes hitting their neighborhoods as they crossed into government-held Aleppo.

Fatima Al Omar made the journey with her five grandchildren; their father was killed two months ago by a bomb.

“We were terrified,” she said. “We just wanted the bombs to stop, and now we want the war to end.”

The family moved into a cold hut in Jibreen, a makeshift shelter on the government side. For the moment, they were safe, but the grandchildren didn’t stop asking where their father was.

Aid workers in the camp tried to make life a little more bearable for the people living there by encouraging them to yell songs at the top of their voices to relieve stress, and to drown out the horror stories many of them have endured.

But erasing the memories of four years of suffering was not going to be so easy, a fact Fatima Al Hamoud knew all too well. At one hundred years old, she had a century of memories behind her.

“Poor Syria. Poor Syria,” she cried. “My heart is broken for poor Syria.” She never imagined her final years would be spent like this, Patta reports.

And with the Syrian and Russian army bombing day and night, many more civilians were expected to attempt the dangerous crossing from rebel-held areas to the government controlled side, Patta says.

Meanwhile on Monday, rebel shelling of Syrian government-held part of Aleppo killed a Russian nurse in a makeshift Russian hospital, and the Defense Ministry in Moscow said a Russian fighter jet crashed into the Mediterranean Sea after returning from a sortie over Syria.

The developments were a blow to Russia, which has been one of the staunchest supporters of Syrian President Bashar Assad in his country’s bitter civil war, now in its sixth year.

The shelling in Aleppo that killed the female nurse also wounded two Russian doctors working in the field hospital, a Russian officer in Aleppo told reporters. He spoke on condition of anonymity in line with regulations. The hospital equipment was part of aid that Moscow had sent into the Furqan neighborhood in the government part of Aleppo the previous day.