Fighting rages in Syria's Aleppo

REUTERS CANNOT INDEPENDENTLY VERIFY THIS VIDEO WHICH WAS OBTAINED FROM SOCIAL MEDIA

Activists say this amateur video shows rebels in a firefight with government forces in the Syrian city of Aleppo on Friday.

The video was uploaded to a social media website and Reuters cannot independently verify the content.

Fighting is raging throughout Aleppo, a key battleground in Syria's 17-month conflict, which has pitted rebels against forces loyal to president Bashar al-Assad.

Meanwhile, another amateur video shows a fire-damaged hospital in the capital, Damascus.

Activists say the facility was attacked by government forces.

They also claim that at least four civilians - some with their hands bound - were executed in another part of the capital.

The U.N. says 1,600 people were killed in Syria last week, the highest weekly figure since violence erupted last year.