Hundreds of sick or wounded Syrians and their families were being evacuated from besieged rebel- and regime-held towns for treatment Thursday as relief efforts intensified even as peace talks falter, AFP reports.

The evacuees, who were "in urgent need of life-saving medical attention," according to the United Nations, were bused out of their enclaves late on Wednesday in a joint operation with the Syrian Arab Red Crescent.

In a carefully synchronized operation, they were all brought to a staging area in a rebel-held part of central Syria at dawn on Thursday before being transported on for treatment, the Syrian Observatory for Human Rights said.