US President Joe Biden is monitoring the "extraordinary events" in Syria, the White House has said.

We will bring you more reactions to the developments in Syria as we get them.

Lina Shaikhouni
BBC World Service

Residents inside Damascus are still trying to comprehend the events that have transpired in the country over the past few hours.

“For the very first time, there is a true feeling of freedom,” one resident tells me.

“It’s a feeling we had not experienced before, and it’s surprising us,” he says.

He’s asked to remain anonymous for security reasons.

Videos have been circulating online showing some residents in central Damascus celebrating the fall of the government of Bashar al-Assad.

“The streets outside are filled with celebrations. In the central Umayyad Square, people are celebrating in a way that is so peaceful. They’re shooting fireworks. Yes we are hearing some gunshots, but it’s mostly fireworks,” he notes.

“What we’re feeling really resembles what we felt during the revolution when it began in 2011. This is the continuation of a dream that had started that year.”

Image source, Getty Images

He notes that everyone is in disbelief that this all happened without intense battles or killings. Still, he notes, there are worries and fears about the future and what it holds.

However, he feels that today is not a day to worry.

“Today, all the Syrian people will only celebrate. No-one wants to think about tomorrow. We only want to celebrate now.”

Syria's prime minister says that he remains in Damascus and that he is ready to help to do what is best for the people.

In a speech broadcast on social media, Mohammed Ghazi al-Jalali also said that Syria "can be a normal country that builds good relations with its neighbours and the world".

Syrians have been cheering as rebel forces launched successful offensives in major cities over the past week-and-a-half. On Sunday, similar scenes of celebration were seen in Damascus as they entered, and President Bashar al-Assad was reported to have fled.

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Lina Shaikhouni
BBC World Service

Millions of Syrians who had been forcibly displaced outside the country have taken to social media to celebrate the end of President Bashar al-Assad’s decades’ long rule over the country on 8 December.

“Oh God, I cannot stop crying. I am imagining the day I go back,” Human Rights Activist Rima Flihan writes on her Facebook page.

Syria has seen the world’s largest refugee crisis, according to the UNHCR. The organisation estimates that around 6.6 million Syrians were forced to flee their homes since 2011.

“How lonely is this feeling of happiness when we are all scattered [across the world]”, one user on Facebook posted.

As updates keep coming in until the early hours of 8 December, many say they cannot sleep.

“How does one sleep, when their nation is being liberated,” one user says.

Most have expressed their disbelief at the fast pace of events.

As the opposition forces arrived in Damascus, many users posted videos of themselves celebrating, and shedding tears of joy.

Many celebrated especially when news came out that opposition forces took over the notorious Saydnaya prison near Damascus, and freed tens of thousands of political detainees held there. “This is the day we all waited for,” one user writes.

“Syria is now for Syrians,” another says.

Image source, Reuters

Syria's opposition leader, Hadi al-Bahra, has told the Arabic news organisation Al-Arabiya that the Assad regime has fallen and that a "dark era in Syria's history has passed".

Bahra - who leads the National Coalition of Syrian Revolution and Opposition Forces - has stressed to the public that the situation in Damascus is safe.

"To our people of all sects and religions, as long as you do not raise arms against any other citizen and as long as you stay in your homes, you are safe," he wrote on X.

"There will be no cases of revenge or retaliation, and no violations of human rights. People's dignity will be respected and their dignity will be preserved."

Rim Turkmani, director of the Syria Conflict Research Programme at the London School of Economics, spoke to BBC News about the fast-moving developments in Syria.

Rebel group HTS is set to broadcast its first message to the public on Syrian television shortly.

The group said earlier on Sunday that it was seizing control of the radio and television headquarters in Damascus to broadcast its victory announcement.

The official state television broadcast stopped after rebel forces entered the capital.

Rebel forces have been making a number of new announcements about the situation in Syria, now that President Bashar al-Assad appears to have fled the country.

The leader of the Islamist militant group Hayat Tahrir al-Sham (HTS) has announced on Telegram that it is forbidden for military forces in the city to approach "public institutions" in Damascus.

Abu Mohammed al-Jolani adds that these institutions "will remain under the supervision of the former prime minister until they are officially handed over".

Earlier we heard from Natasha Hall, a Middle East expert at the Center for Strategic and International Studies, who said she believes we are witnessing the end of the Assad regime in Syria.

When asked what the dynamics are within the rebel forces who appear to have driven President Assad out, Hall said that the Islamist group Hayat Tahrir al-Sham (HTS) has led the charge and is the “most disciplined and powerful” of all the groups involved.

She also says they appear to be the most independent of foreign forces, with other rebel factions operating under Turkey’s influence.

“It remains to be seen how coordination is going to go between these groups, especially Kurdish-operated groups in the north-east”.

There is deep-seated hostility between the Turkish state and the Kurds, who are stateless.

Rebel forces have declared Syria "free", saying the "tyrant" President Bashar al-Assad has left.

It is the end of a dark era and the beginning of a new one, HTS says on Telegram.

People who were displaced or were imprisoned by the Assad regime's half-century reign can now come home, the rebels say.

It will be a "new Syria" where "everyone lives in peace and justice prevails", HTS says.

There are reports of celebrations starting in Umayyad Square, a landmark in the heart of Damascus home to important government agencies, including the Ministry of Defence and the Syrian Armed Forces.

A video circulating on social media shows music being blasted and about a dozen people dancing around a tank reportedly abandoned by the military.

Syrian defence ministry officials have reportedly withdrawn from their headquarters in Damascus.

Here's a catch-up on fast-moving developments in Syria:

• Syrian President Bashar al-Assad has left Damascus by plane to an unknown location, Reuters reports, quoting two Syrian officials

• Reports of his departure come as rebel group HTS say they have begun entering the Syrian capital
• The rebels also say they have freed inmates from Saydnaya prison where thousands of opposition supporters are said to have been tortured and executed
• Hezbollah, which is backed by Assad ally Iran, has withdrawn its soldiers from certain areas
• Earlier, the rebels entered Syria's third-largest city, Homs

Image source, Reuters

Natasha Hall is a senior fellow with the Middle East Program at the Center for Strategic and International Studies.

She told BBC Radio 5 Live that “it’s really looking like we’re in the final hours, if not minutes, of 54 years of tyranny in Syria”, referring to the rule of the Assad family, which began in the early 1970s.

Hall added that it appears President Bashar al-Assad has left Damascus, as we have been reporting.

She says what is unfolding in the country is the result of a confluence of events, which includes the fact that Assad’s allies, including Iran and Russia, have been “weakened and distracted” by other events in the world.

Added to this is the fact that that 90% of people in Syria were living under the poverty line and many are living in limbo in displacement camps.

“I think people were growing tired,” Hall said.

Hugo Bachega
Middle East correspondent, near Turkey-Syria border

A lot of people will be happy to see President Assad go, but there is the obvious question about what happens next.

This insurgency is being led by Islamist rebels from a group known as HTS. Their roots are in al-Qaeda and, for years, they have been trying to rebrand themselves as a nationalist force. But many are not convinced, and say they remain an extremely violent organisation and concerned about what might come next.

Syrian President Bashar al-Assad has boarded a plane and left Damascus to an unknown destination, Reuters news agency has just reported quoting two senior Syrian officers.

The SOHR war monitor also says a private plane that has left Damascus airport was likely carrying Assad. Government troops at the airport were discharged after its departure, it said.

This comes as rebel forces say they have started entering the Syrian capital.

Rebels have reportedly freed from the infamous Saydnaya, a prison once described by the UN as a "human slaughterhouse", where thousands of opposition supporters are said to have been tortured and executed. Thousands more could currently be detained.

HTS announced on Telegram that the prisoners have been freed, calling it "the end of the era of injustice" in Saydnaya. Unverified videos circulating on social media appear to show people streaming out of the prison grounds.

The Association of Detainees & The Missing in Sednaya Prison said that the released detainees were heading to Manin, a town near Damascus.

"Our forces have begun entering the capital Damascus," the rebels said on their Telegram channel.

Since the Islamist-led group HTS launched its offensive less than two weeks ago, they have taken control of major Syrian cities.

It's unclear where Syrian president Bashar al-Assad is - his office said that he was still at work in Damascus, but he has not been seen.

We are also hearing reports that the militant group Hezbollah, which is backed by Iran - an ally of Syrian President Bashar al-Assad - is withdrawing its soldiers from certain areas.

A source close to the group has told the AFP news agency that Hezbollah fighters are withdrawing from the cities of Homs and Damascus.

Reuters is reporting that the group has also retreated from the western city of Qusair, near the Lebanese border.

UK-based war monitor the Syrian Observatory for Human Rights (SOHR) reports that hundreds of members of the Syrian army and security forces have been seen taking off their military uniforms after being told that they were being discharged as the regime had fallen.

Orders had reportedly been issued to them to withdraw from Damascus International Airport following the departure of a private plane.