What's happening in Syria?
- 20 February 2015
The violence in Syria began in March 2011. The middle eastern country has been crippled by a brutal civil war.
Since then, the United Nations estimates more than 200,000 people have died in the clashes between President Bashar al-Assad's government and rebel forces who want him out.
The UN's Refugee Agency says 3.7 million people have fled Syria to neighbouring countries, and over half of those refugees are children.
In July 2012, the International Red Cross said the violence in Syria had become so widespread that it was in a state of civil war.
But what are the reasons behind the violence? And what is being done to stop it getting any worse?
How did it all start?
The trouble began in 2011 in the Syrian city of Deraa.
Locals took to the streets to protest after 15 schoolchildren were arrested - and reportedly tortured - for writing anti-government graffiti on a wall.
The protests were peaceful to begin with, calling for the release of the children, democracy and greater freedom for people in the country.
The government responded angrily, and on 18 March 2011, the army opened fire on protesters, killing four people.
The following day, they shot at mourners at the victims' funerals, killing another person.
People were shocked and angry at what had happened and soon the unrest spread to other parts of the country.
What do the protesters want and what have they got?
At first the protesters just wanted democracy and greater freedom.
But once government forces opened fire on peaceful demonstrations, people demanded that the President, Bashar al-Assad, resign.
President Assad refused to step down.
As the violence worsened he offered to change some things about the way the country was run, but the protesters didn't believe him.
President Assad also has quite a lot of people in Syria that still support him and his government.
Who are the rebel fighters?
There isn't a clear single group of rebels, united against President Assad.
The opposition, who all want the president to step down, is split between groups of rebel fighters, political parties and people living in exile, who cannot return to the country.
It's thought there could have been as many as 1,000 groups opposing the government since the conflict began, with an estimated 100,000 fighters.
The Rise of IS
The war is now more than just a battle between those for or against President Assad.
IS is a radical militant group which has used violence against anyone who doesn't agree with their extremist views.
IS later moved into eastern Syria and in the chaos of war they were able to gain land and power there too.
Chemical weapons have been used during the war, causing anger around the world.
In August 2013, a chemical attack just outside the Syrian capital, Damascus, caused a strong reaction from many countries including America, Britain and France.
After the effects of these weapons were seen, there were long discussions over what the rest of the world should do.
In September 2013, United Nations inspectors confirmed that chemical weapons had been used in Syria, but the report did not say who was responsible.
Syria, however, denies using chemical weapons, which are banned under international law because the effects of their use are so horrific.
The government in Syria said: "There is no country in the world that uses a weapon of ultimate destruction against its own people."
They blamed the rebel forces for the chemical attack.
Destruction of chemical weapons
The chemical attack caused international outrage and many leaders argued it demanded a strong response.
The American and French governments discussed limited missile strikes against military targets in Syria.
But Russia has strong ties with President Assad's Syrian government and has helped Syria in the past by supplying weapons.
In September 2013 Russia suggested a solution that could avoid a wider conflict: that the Syrian government should give up its chemical weapons and commit to destroying them so they can never again be used.
The process of destroying the weapons began in October 2013, and the people working on this project were awarded the Nobel Peace Prize later that month.
The refugee crisis
Many ordinary Syrian people have been caught up in the violence during the war and have been forced to leave their homes to escape to safety in other countries.
Every day refugees stream across the borders of Syria into the neighbouring nations of Jordan, Lebanon, Turkey and Iraq.
More than 3 million people have fled Syria since the start of the conflict, most of them women and children. It is one of the largest refugee movements in recent history.
A further 6.5 million people, 50% of them children, have had to leave their homes within Syria.
They are in desperate need of help. But aid agencies say that getting aid to people inside Syria is very difficult and dangerous.
Some people are now searching for a new life in Europe. In 2014, 6,000 Syrians walked across the border from Turkey to Bulgaria and are living in deserted buildings, like former schools.
What happens next?
It doesn't look like the fighting is likely to end any time soon.
There is a stalemate between the two sides: the government forces and the rebel groups are unable to defeat each other.
In December 2013, the US and Britain stopped all 'non-lethal' supplies to the Syrian rebel groups too. Non-lethal supplies means things like medicine, vehicles and communication equipment.
Both the Syrian government and rebel groups are now also having to fight back against the terrorist group Islamic State,
Caught in the middle of these wars, the Syrian people have lost their homes and members of their family. Many are living in makeshift camps.
Lots of countries are continuing to supply aid, such as food and emergency supplies, but the US and Britain said they had to stop all other support as they feared the equipment may be stolen by rebel groups, which they did not support.
For now, discussions continue between powerful nations like the US, Russia, Britain and France, to try to work out if there is another way to help Syria achieve peace.