What's happening in Aleppo?

                                      

 The northern Syrian city of Aleppo has been caught in a four-year deadlock - but that has now been broken.

Aleppo has been a key battleground in the war between forces loyal to President Bashar al-Assad and rebels who want to overthrow him.

Since November, Syrian government forces have rapidly retaken almost all of the opposition-held east, leaving the rebels on the brink of defeat.

Tens of thousands of civilians have fled those districts, but the UN says hundreds have gone missing since crossing into government-controlled areas - and that rebels are preventing some civilians from leaving.

Meanwhile many of those in the areas seized by troops are suffering serious food and fuel shortages.

Much of Aleppo's ancient souk in the Old City has been damaged or destroyed

As the battle for Aleppo heads towards a conclusion, people trapped in a small area of east Aleppo still held by the rebels have been sending harrowing messages with their final goodbyes.

As the bombing by Syrian government forces intensified, the calls for help from those trapped in rebel-territory have grown more desperate.

Lina, an activist tweeting last night, makes this desperate plea: "Humans all over the world, don't sleep! You can do something, protest now! Stop the genocide".

How the rebels have lost ground in 2016

4 Jan: At the start of the year, the rebels hold eastern Aleppo, linked to the border with Turkey via territory to the north and west. Turkey's government is a key backer of the rebellion against Mr Assad.

1 Aug: By August, government forces surround the rebels, taking control of the strategically-important Castello Road in northern Aleppo, the only route into the rebel-held east. About 275,000 people suddenly find themselves under siege.

22 Aug: Rebels and al-Qaeda-linked jihadist fighters in the countryside outside Aleppo seize back control of a route through the Ramousseh district in the south of the city linking them up with the outside world.

17 Oct: Government forces retake the area in early September and resume the siege. There is a brief pause in the offensive in mid-October to allow civilians and rebels to leave, but few take up the offer.

28 Nov: Syrian government forces recapture more than a third of rebel-held territory in eastern Aleppo. The rebels lose all of the northern neighbourhoods, leaving them with under two-thirds of the territory they had in the city.

6 Dec: Troops advance further, seizing more districts in the east. The gains mean the government has now recaptured more than 70% of the rebel-held area.

12 Dec: The Syrian army makes more gains, taking several districts, including the key Sheikh Saeed area, from the rebels, leaving them confined to a small enclave.

13 Dec: Following intense bombardment from pro-government forces, the rebels are squeezed into ever smaller areas of the city, retreating into just a handful of neighbourhoods. Russia's ambassador to the UN later says that military action has ended in eastern Aleppo.

After the government resumed its air campaign on 15 November, troops pushed into several northern Aleppo districts and forced rebels and jihadists to retreat southwards. Tens of thousands of civilians fled their homes.

By 13 December, more than 90% of the city had fallen to the government. The UN warned up to 100,000 people were trapped in "ever-shrinking" areas of eastern Aleppo, adding that rebels were stopping people from leaving.

Food and fuel in the city are running out, and basic infrastructure and health care have been obliterated - at one point in November, all hospitals in eastern Aleppo were virtually out of action as a result of air strikes.

The UN says hundreds of civilians have died, but the government and Russia have denied targeting them. Rebel rocket and mortar fire has also killed dozens of people in the government-controlled west.

Source: BBC