Thousands of black-robed Turkish lawyers stormed out of their courthouses Wednesday, shouting about the rough treatment police dished out to their colleagues amid Turkey's biggest anti-government protests in years.

The rallies by clapping, chanting jurists added a new twist to the nearly two weeks of protests that started in Istanbul and spread to dozens of other Turkish cities. The protests have shaped up as the biggest test yet in the 10-year rule of Prime Minister Recep Tayyip Erdogan and his Islamic-rooted government.

Police and protesters mostly retrenched Wednesday after fierce overnight clashes in Istanbul's Taksim Square — a hiatus before officials were to host talks with some protesters later in the day.

• The last tweet from the account of CBC reporter Sasa Petricic, who is in Istanbul covering the protests, said "Arrested." CBC News is trying to determine what happened and will provide more information when it is available.

Protesters say the prime minister is becoming increasingly authoritarian and is trying to force his deep religious views on all Turks, a charge that Erdogan and his allies strongly deny.

In Ankara and Istanbul, thousands of lawyers railed against the alleged rough treatment of dozens of their colleagues, who police briefly detained in Istanbul on the sidelines of Tuesday's unrest.

Sema Aksoy, the deputy head of the Ankara lawyer's association, said the lawyers were handcuffed and pulled over the ground. She called the police action an affront to Turkey's judicial system.

"Lawyers can't be dragged on the ground!" the demonstrating lawyers shouted in rhythm as they marched out of an Istanbul courthouse. Riot police stood off to the side, shields at the ready.

Turkey's Human Rights Foundation said the Istanbul Public Prosecutor's office had launched an investigation into allegations of excessive use of police force during the protests.

The foundation said 620 people, including a one-year-old baby, were injured during the police crackdown early Wednesday. Police detained some 70 people during the incidents. Prior to this, activists reported that 5,000 people had been injured or seriously affected by the tear gas and four people have died from the protests.

Activists doubt legitimacy of scheduled talks

The government, meanwhile, pressed ahead with uncertain efforts to defuse the protests.

President Abdullah Gul, seen by many as a more moderate voice than Erdogan, said the government could not tolerate more of the unrest that has disrupted daily life in Istanbul and beyond. He promised, however, that authorities would listen to protesters' grievances.

"I am hopeful that we will surmount this through democratic maturity," Gul told reporters. "If they have objections, we need to hear them, enter into a dialogue. It is our duty to lend them an ear."

It was unclear exactly who would be taking part in the meeting Wednesday afternoon at the offices of Erdogan's Justice and Development party in Ankara — and whether the meeting will be able to broker an end to the protests.

• CBC News brings you the latest from Taksim Square
• Unrest in Turkey: key players, major developments

Activists had doubts about the talks' legitimacy. Only an actor and a singer — with unclear connections to the protesters — had agreed to take part, and some leaders of civil society groups, including Greenpeace, had said they would not participate because of an "environment of violence" in Turkey.

Hundreds of protesters remained camped out in Gezi Park following violence between police and activists. (Osman Orsal/Reuters)

The activist group Taksim Solidarity, which includes academics and architects who oppose the redevelopment plan at nearby Gezi Park, said its members hadn't been invited to the meeting with Erdogan and predicted it would yield no results.

"As police violence continues mercilessly ... these meetings will in no way lead to a solution," the group said in a statement.

The group reiterated its demands, saying Gezi should remain a public park, senior officials behind the police excesses should be fired and all detained protesters should be released.

Riot police stood off to the side

After Tuesday's violence, traffic returned to Taksim Square with taxis, trucks and pedestrians back on the streets. At one point, some police were seen kicking a soccer ball on the square. Riot police stood off to the side, near a new barricade of wrecked cars and construction material that activists erected before dawn to prevent police from firing tear gas into the square's still occupied Gezi Park.

Hundreds of protesters remained camped out in Gezi Park, clearing up after a night of trying to fend off tear gas, followed by an early morning storm that blew down tents and soaked bedding.

On Tuesday, riot police firing water cannons and tear gas clashed all day and night with pockets of protesters throwing stones and setting off fireworks. The pitched battles didn't simmer down until just before dawn.

Erdogan has insisted the protests and occupations, which he says are hurting Turkey's image and economy, must end immediately and are being organized by extremists and terrorists.

The protests are drawing expressions of concern from abroad.

Germany's government was "following the news from Turkey with great preoccupation, especially the images of yesterday's police action," Chancellor Angela Merkel's spokesman Steffen Seibert said Wednesday. "Now de-escalation is needed. Only an open dialogue can contribute to easing the situation."

The protests erupted May 31 after a violent police crackdown on a peaceful sit-in by activists objecting to a development project replacing Gezi Park with a replica Ottoman-era barracks. They then spread to 78 cities across the country and have attracted tens of thousands of people each night.