Can Syria's Kurds realise territorial ambitions?
When the Syrian protest movement started in 2011, it was young Kurds in Amouda, in the north of the country, who took to the streets, calling for freedom and democracy.
President Bashar al-Assad soon announced he would recognise some of the rights demanded by the Kurds and allowed them to register as citizens and hold an identify card, a right they have been deprived of since 1962.
But the Kurds rejected the concessions, saying they would wait to get their rights once all Syrians achieved freedom and democracy.
Five years on the scene is different. As the war has dragged on in Syria, Kurdish groups have taken the opportunity to gain more power.
The PYD (the Democratic Union Party) declared self-administration in the Kurdish region of Syria in November 2013.
Other Kurdish parties formed the Kurdish National Council, which is part of the main anti-Assad opposition group, the Syrian National Coalition.
The PYD is close to the Kurdistan Workers' Party - the PKK - which is banned in Turkey and regarded by many Western governments as a terrorist organisation.
"The PYD had popularity on the ground as they were addressing the Kurdish population's concerns. They are pragmatic and organised, unlike other Kurdish parties who failed to deliver," says Farooq Haji Mustafa, a Syrian Kurd journalist and founder of the Barchav Centre for Media and Freedom, in Gaziantep, southern Turkey.
"The Kurds were attacked by some Islamist groups like Jabhat al-Nusra, therefore they felt they were not part of the Syrian revolution. They thought they should seize the opportunity and protect Kurdish interests.
"The PYD delivered and were supported by regional and international agreements since they were the only force that is reliable in the fight against Islamic State," he added.
But Mr Haji Mustafa says the PYD is a totalitarian party, doesn't like opposition to its rule and has acted violently against some in their community.
The PYD later came to form the Syrian Democratic Forces, along with some Arab tribes, and it's the SDF which has become one of the main powers inside Syria fighting so-called Islamic State (IS) - with support from Western coalition forces.
But there is criticism of the SDF over how they have allegedly acted towards Kurdish opponents and civilians in areas in which they have been fighting.
Some have gone so far as to accuse them of being another face of the Syrian regime.
Shero Alo is an opposition activist from Ifrin in Aleppo province in the north of Syria. He was part of the Kurdish opposition but had to leave his town due to, he said, threats from the PYD.
"They threatened, arrested and beat us up during our protests. Anyone who opposes them is sent to prison. Some have been jailed for two or three years," Mr Alo said.
This view is shared by some Arab activists who say they witnessed abuses in Tal Abyad, a predominantly Arab town on the outskirts of Raqqa, captured from IS last year by the YPG, the military wing of the PYD.
"When the PYD entered Tal Abyad in 2015, they pushed all the Arabs out of their homes," said Ahmad Haj Saleh, who has been documenting the activities of the PYD since 2015.
"They looted and tortured and imprisoned people. They used a hole to bury people alive in the same place that Islamic State fighters used to have mass graves.
"Most of the Arabs who were pushed out were not allowed into certain parts of Tal Abyad and families of the Kurdish fighters now inhabit their houses. The ones who were allowed back needed a Kurdish guarantor before they could get to their own towns," he said.
However, a PYD spokesman, Dr Juan Mustafa, told the BBC that Kurdish forces had not carried out any abuses.
"There are no violations at all in Tal Abyad. All the families who left came back," he said.
"When Syrian Democratic Forces enter a town or an area it is due to calls from the families to come and liberate them from the atrocities of IS."
The PYD/YPG have previously acknowledged what they called some "isolated incidents" of forced displacements.
A picture of alleged abuses has not emerged in the current battle for Manbij - a predominantly Arab city held by Islamic State fighters near their stronghold of Raqqa.
This offensive is being carried out by forces including the US-backed SDF and SDF-allied Manbij Military Council (MMC).
MMC spokesman Shervan Darwish says they are doing everything they can to protect civilians while they push IS out of the city.
"We have nothing to do with who will rule Manbij - or how it will be ruled. The civil council will decide there," he said.
"We are here to protect the civilians and to free their city. It is up to them how to rule it after."
The PYD has made calculations in its own long-term interest. It seized control over most territories with a Kurdish population in Syria and now considers them as a federal region.
It has presented itself as a partner for the international community in fighting terrorism and just recently announced a constitution that would govern what it calls Rojava - the Kurdish areas of Syria - as well as other parts of northern Syria in partnership with some Arab tribes there.
This territorial expansion and new power for the PYD has been supported by the US - who are partners in the fight against IS - and Russia.
But it alarms Damascus and the Turkish government, a foe of President Assad.
Recent reports say that Algeria is brokering talks between Damascus and Ankara over a common Kurdish threat.
Although some believe that the Syrian government helped facilitate the PYD's role in the north at the start of the conflict, the fact that the group has become more powerful now makes Damascus wary.
Turkey does not want a Kurdish state on its own border and the PYD is linked to the PKK - which Ankara blames for many attacks in Turkey.
Need for consensus
While the Kurds have proven to be reliable in the fight against IS in the north of the country, there is some unease about their ambition to separate entirely from the rest of Syria.
Ismail Sharif is a Kurdish journalist from Amouda. He wants a democratic and united Syria and left his town due to fears of reprisal attacks from the PYD.
He still believes it is hard for them to create a Kurdish state and to split the country.
"Unfortunately now there is a proxy war and there are many dictators in Syria. I don't think there will be a division of Syria," he said.
"The PYD cannot rule one area from Kobani to Ifrin with many Arab towns and villages in the middle.
"They cannot continue ruling across this area without an agreement between all Syrians in a free and democratic country that ensures equal and full rights for all its citizens."