Most of the 148 evacuees were disabled or in need of urgent mental care, the International Committee of the Red Cross (ICRC) said on Thursday. Elderly orphans and people with mental health issues were also among the trapped civilians.

Activists from the Red Cross and the Syrian Arab Red Crescent (SARC) managed to reach the people after the government forces pushed the rebels out of the historic Old City.

"These patients and civilians had been trapped in the area for days because of heavy clashes nearby and as the front line kept drawing closer," said chief ICRC delegation in Syria, Marianne Gasser.

Rescue too late for some

With the Syrian army pushing into the rebel-held areas, the patients were "forgotten" in a building that once served as a home for the elderly, Red Cross' communication coordinator Pawel Krzysiek said. The activists managed to transport them into government-controlled hospitals and shelters in the west of the city.

"Tragically, for some, the operation came too late: 11 people died before the SARC and ICRC teams were able to reach the centre," the Red Cross said in a statement.

"They were either caught in the crossfire or died because they did not have access to the right medications."

Rebels are quickly losing ground in Aleppo, with regime forces now controlling over 80 percent of the former militias' stronghold. The three-week offensive has claimed almost 500 civilian lives across the city, as two sides trade artillery fire and Russian and Syrian air force  target the remaining rebel positions.

'There is nothing left'

Syrian opposition activists reported heavy bombing on Thursday.

In an emotional statement, the head of the eastern Aleppo medical authority called for an immediate ceasefire, saying that the city was "finished."

"There is nothing left except a few residents and bricks," Mohammed Abu Jaafar said in an audio message. "This may be my last call."

On Thursday, the US and Turkey independently announced they were  negotiating with Moscow  and hoping for a break in fighting. A day earlier, however, Bashar al-Assad declared that the chances for a truce were "practically non-existent."

dj/kms (dpa, AP, AFP, Reuters)