The Syrian Observatory for Human Rights said a first group of prisoners were freed on Thursday following an outbreak of tuberculosis.

The area where the prison is located, in the outskirts of the city of Aleppo, has been under siege for the past eight months by militant groups loyal to al-Nusra Front and other terrorist groups.

The prison is said to be hosting more than 3,000 prisoners.

Tens of thousands of people have been detained in Syria since the uprising broke out in March 2011.

The northern province of Aleppo is currently covered in snow and it is so hard to provide food and drug items for the detainees.

The UN food aid agency on Friday warned the humanitarian crisis in Syria was growing, as it detailed plans to airlift the first supplies in five months into the conflict-torn northeast of the country.

The Rome-based World Food Program said that as soon as bad weather clears two chartered planes from Iraq would begin flying in 400 tons of food to the Al Hassakeh governorate, which cannot be reached by road.

In an operational update, the organization said plans to provide food air to four million people this month across Syria were "on track" despite bitter weather.

NJF/NJF