Thousands of students flooded the streets of Istanbul on Monday, marking a new chapter in the protests ignited by the arrest of opposition Mayor Ekrem Imamoglu.

The demonstrations, which started after Imamoglu’s arrest on March 19, had spread to at least 55 of Turkey's 81 provinces, leading to violent clashes with riot police and widespread international condemnation.

More than 1,130 people had been arrested in the previous six days, including 43 detained on Monday night, as confirmed by Turkey’s Interior Minister. Among the detainees were several journalists, including an AFP photographer, caught up in the unrest.

Imamoglu, a 53-year-old politician from the opposition Republican People's Party (CHP), had been widely regarded as the most formidable challenger to President Recep Tayyip Erdogan in upcoming elections. In just four days, the mayor was removed from office after being jailed, interrogated, and implicated in a graft and terror probe.

On Monday, students from both Istanbul and Ankara joined the growing protests, staging walkouts from their university lectures to take part in rallies. In Istanbul, crowds of chanting students carrying flags marched towards Besiktas, a prominent port on the Bosphorus, where local residents offered applause and clanged saucepans in solidarity. They later continued their protest to the historic peninsula, where they joined the ongoing demonstration outside City Hall.

"This is not a meeting, this is an act of defiance against fascism!" CHP leader Ozgur Ozel told the enthusiastic crowd, as they waved banners. One sign read, "Palaces are yours, the streets are ours," directed at Erdogan, while Ozel also called for a boycott of pro-government media and businesses aligned with the government.

After a cabinet meeting earlier that day, President Erdogan accused opposition forces of inciting the protests, urging them to "stop playing with the nation's nerves." He also maintained that the Turkish economy was under control, despite the fallout from Imamoglu’s arrest, which had significantly damaged the Turkish lira and sparked volatility in the financial markets. The benchmark BIST 100 stock index had plunged nearly 8 percent on Friday, but made a modest recovery on Monday, ending the day around 3 percent higher.

Imamoglu’s arrest followed his overwhelming selection by the CHP as its candidate for the 2028 presidential elections. Political observers speculated that this looming challenge to Erdogan’s leadership was the real motive behind the crackdown.

Germany strongly condemned the arrest, calling it "totally unacceptable," while neighbouring Greece warned against actions that threatened civil liberties. The European Union also cautioned Ankara to uphold "democratic norms," with France’s foreign ministry describing Imamoglu’s detention as a "serious attack on democracy."

In a separate development, the arrest of Turkish journalists on Monday was condemned by multiple press organisations. According to the MLSA rights group, ten journalists, including the AFP photographer, had been detained before dawn for covering the protests. The Journalists' Union of Turkey and the Turkish Journalists Association issued a joint statement demanding an end to the harassment of reporters. "Stop targeting journalists!" they said, noting that many had been subjected to police violence, tear gas, and plastic bullets while documenting the protests.

Reporters Without Borders (RSF) also called for the immediate release of the detained journalists. Erol Onderoglu, RSF’s Turkey representative, expressed concern over the escalating crackdown on the media.

Imamoglu’s wife, Dilek Kaya Imamoglu, voiced her opposition to the arrest of journalists, stating on social media, "What is being done to members of the press and journalists is a matter of freedom. None of us can remain silent about this."

From his jail cell, Imamoglu sent a resolute message via his legal team, denouncing the legal actions against him as a "political execution without trial." He declared, "I wear a white shirt that you cannot stain. I have a strong arm that you cannot twist. I won’t budge an inch. I will win this war."