Turkey has seen a second day of running battles between police and protesters, with demonstrators taking over a central square in Istanbul.
Riot police pulled back on Saturday after being accused of heavyhanded tactics, but there were fresh clashes near the offices of the Turkish prime minister, Recep Tayyip Erdogan.
The unrest has spread to other cities across the country, with police on Saturday blocking a group of demonstrators from marching to parliament and the prime minister's office in Ankara.
Stone-throwing protesters clashed with police in the Kizilay district of the Turkish capital as a helicopter fired tear gas into the crowds.
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Riot police with electric shock batons chased demonstrators into side streets and shops.
There were also protests in the Aegean coastal city Izmir.
During the day, crowds of protesters in Istanbul chanting "shoulder to shoulder against fascism" and "government resign" marched on Taksim Square in one of the largest demonstrations against Erdogan's government.
Clashes raged on during the night, with thousands of people marching through Turkey's largest city, some banging pots and pans as residents shouted support from the windows.
Others held up cans of beer in defiance of the recent alcohol law passed by the Islamist-rooted ruling Justice and Development Party (AKP) that would bring severe restrictions to the sale and advertising of alcohol.
What began as an outcry against a local development project in Istanbul has escalated into widespread anger against what critics say is the government's increasingly conservative and authoritarian agenda.
The restrictions on alcohol sales and warnings against public displays of affection in recent weeks have also led to protests.
Concern that government policy is allowing Turkey to be dragged into the conflict in neighbouring Syria by the West has also sparked peaceful demonstrations.
As night fell on Saturday, broken glass, rocks and an overturned car littered Taksim Square, where hundreds were injured in clashes the day before.
A helicopter buzzed overhead as groups of mostly young men and women, bandanas or surgical masks tied around their mouths, used Facebook and Twitter on mobile phones to try to organise and regroup in side streets.
Police clashed with protesters who lit fires in the streets leading to Erdogan's Istanbul office.
Muammer Guler, interior minister, said police had detained 939 protesters in over 90 demonstrations in 48 cities, adding that some of them were released after giving testimonies.
He said 53 citizens and 26 police officers were injured in the protests.
One of the injured civilians was in intensive care unit at an Istanbul hospital, Guler said.
The Istanbul protest began late on Monday as a peaceful sit-in at Gezi Park across Taksim Square. The demonstrators had been preventing workers from razing some of the park's 600 trees, the last patch of green in the commercial area, to make way for the restoration of Ottoman-era military barracks.
Residents fear that the barracks will be turned into a shopping mall.
The demonstration soon took a violent turn, however, with police shooting rounds of tear gas to disperse the protesters.
|Al Jazeera's Isil Sariyuce reports on the opposition's growing fears over limits on personal freedoms
Earlier on Saturday, thousands of protesters in Istanbul celebrated a victory as police withdrew from Taksim Square.
"Government, resign!" protesters shouted as riot police pulled back from area.
"We are here Tayyip, where are you?" they cried, shouting taunts aimed at the prime minister.
The protesters, including artists and political party representatives, were dancing and singing while some launched fireworks in celebration.
Mevlut Cavusoglu, AKP's vice president of foreign affairs, told Al Jazeera that protests turned violent with demonstrators attacking police cars and destroying property.
But he admitted that police officers used "excessive force" against demonstrators and said it would be investigated.
"It is true police used excessive force and this is not acceptable," he said.
"We cannot accept this because we have been trying to democratise this country."
Erdogan also admitted on Saturday there may have been some cases of "extreme" police action.
"I call on the protesters to stop their demonstrations immediately," he said in a televised.
"It is true that there have been some mistakes, extremism in police response."
The interior ministry said legal action would be taken against police officers acting "disproportionately".
Erdogan, however, remained defiant, pledging to push forward with the plans to redevelop Taksim Square.
|Protesters have included a broad spectrum of people opposed to what they call Erdogan's increasingly conservative agenda
"If this is about holding meetings, if this is a social movement, where they gather 20, I will get up and gather 200,000 people. Where they gather 100,000, I will bring together one million from my party," he said.
"Every four years we hold elections and this nation makes its choice.
"Those who have a problem with government's policies can express their opinions within the framework of law and democracy."
For his part, Abdullah Gul, Turkey's president, said the protests had reached a "worrisome level" and called on police and the demonstrators to act with restraint.
Local media reported that Istanbul police were running short of tear-gas supplies, and that the units had been warned to use the gas sparingly.
Erdogan said the redevelopment of Gezi Park was being used as an excuse for the unrest and warned the main opposition Republican People's Party (CHP), which had been given permission to hold a rally in Istanbul, against stirring tensions.
The protests so far have included a broad spectrum of people opposed to Erdogan and do not appear to have been organised by any political party.
CHP officials have called on its members not to take party flags with them to the protests, apparently concerned they would be held responsible for the violence.
Kemal Kilicdaroglu, the party's leader, has accused Erdogan of behaving like a dictator. "Tens of thousands are saying no, they are opposing the dictator," he said.
"The fact that you are the ruling party doesn't mean you can do whatever you want."
Al Jazeera's Rawya Rageh, reporting from Taksim Square on Saturday, said there was growing momentum against Erdogan.
"What protesters are telling us here is that they are angry about what they are describing as the stubborn reaction of the prime minister and the heavyhanded tactics of his police force.
"The protesters have been directing their anger both at the PM and also at the media. They say the media has sold out and is not covering these events."
The US State Department said Turkey should uphold "fundamental freedoms of expression, assembly and association, which is what it seems these individuals were doing".
The British foreign office urged Turkey "to exercise restraint and not to use tear gas indiscriminately".