Turkish police clashed with protesters around Istanbul's main Taksim Square on Tuesday and 170 people were detained as they gathered to mark the anniversary of nationwide anti-government demonstrations that began nine years ago in nearby Gezi Park.
The 2013 demonstrations were the biggest popular challenge to then-Premier Tayyip Erdogan's rule. Erdogan, who is now president, has equated the protesters with Kurdish militants and those accused of orchestrating a coup attempt in 2016.
A Turkish court sentenced eight people to jail last month, including philanthropist Osman Kavala, finding them guilty of organising and financing the so-called Gezi protests.
They denied the charges, saying anti-government demonstrations erupted spontaneously nationwide and were protected by constitutional rights.
Some 1,000 people gathered on streets near Taksim Square on Tuesday evening, carrying pictures of those who were sentenced to jail.
They also held up pictures of those who died when police intervened in 2013, as well as a banner reading, "The darknes will go away, Gezi will remain."
The crowds were blocked by riot police carrying shields when they attempted to walk to Taksim Square and the main Istiklal Avenue. They also used tear gas to disperse the groups.
"Erdogan is going to go. There is no other way," the protesters chanted.
Earlier, smaller groups of people clashed with police in other areas near Taksim as they attempted to walk to the square.
Social media posts showed people hiding in a building after being affected by the tear gas and police standing outside the shuttered doors.
Istanbul governor's office said 170 people were detained on Tuesday. It said the protests were unauthorised and the Beyoglu area was not designated by law as a place where demonstrations and marches can take place.
Earlier in the day, members of parliament from the Workers' Party of Turkey (TIP) hung a giant banner from one of the bridges spanning the Bosphorus.
After a scuffle, police took down the banner that read "Everywhere is Taksim, everywhere is resistance" - a popular slogan during the 2013 protests.
Ankara's Western allies, rights groups and Europe's top human rights court say last month's court decision and jailings were politically motivated and meant to intimidate Erdogan's opponents.
Critics say the verdict was aimed at criminalising Gezi and creating the perception that protesters were funded by foreign powers.