Thousands of Turks are expected to raise protests on Thursday’s undemocratic detention of Istanbul Mayor Ekrem Imamoglu, despite bans of gatherings, police roadblocks and dozens of detentions on social media posts.

President Tayyip Erdogan’s main political rival, Imamoglu, was arrested Wednesday on charges of grafting and helping terrorist groups, a move that was denounced by the opposition as a “coup attempt” and sparked initial demonstrations.

The move against the popular two-term mayor, which has been subjected to months of legal crackdowns on opposition figures across the country, has been criticized as a politicization attempt to undermine their election prospects and silence.

“We must oppose this evil,” Imamoglu said on social media platform X, calling on the judiciary and Erdogan’s ruling party members to fight injustice.

“These events have transcended our political party and political ideals. Now, the process is about our people, your family. It’s time to raise our voices,” he said.

The government has denied the charges and warned against linking Erdogan or politics to Imamogru’s arrest, after which it imposed a four-day ban on gatherings and restricted access to certain social media to limit communication.

Police locked off-road on Thursday and stationed with water cannons at the police station where the mayor is being held and other parts of the largest city in Tukuye.

“They hurriedly detained our mayor and we elected the ballots with our vote,” opposition supporter Ali Izar said on his way to work in central Istanbul. “I don’t think it’s democratic practice, I condemn it.”

Despite the sharp containment of civil disobedience in Turkey since the national Gaz Park protest against the Erdogan government in 2013, which has caused a crackdown in violent countries, thousands of protesters took to the streets and university campuses on Wednesday in Istanbul, Ankara and other cities.

The crowd chanted anti-government slogans, and among the main municipal buildings in Istanbul, they hung banners of Imamoglu and Mustafa Kemal Ataturk, founding leader of the United States, along with the Turkish flag.

Social media suppression

Imamoglu, 54, led Erdogan’s detention in some opinion polls, is a few days before his Republican People’s Party (CHP) to elect his next presidential candidate.

“People will respond again,” said Yusuf Demirci, another Imamoglu supporter in Istanbul. “As you saw yesterday, everyone is on the street and on the square. The square and the ballot box will be the result of this. I said the righteous will win.”

The detention triggered a crash and partial recovery rate in the lira currency on Wednesday, with a value of $38 by Thursday, compared with a prior 36.67. Bank share fell in particular on Istanbul Bourse, amid concerns about eroding the rule of law and concerns about slowing down the pace.

Interior Minister Ali Yerlikaya said that after the detention, 37 people were detained and charged with “provocative social media posts inciting crime and hatred”, and about 261 social media accounts were also found, including 62 foreign social media accounts.

According to the Office of the Chief Prosecutor of Istanbul and the Financial Crime Investigation Report, the authorities also seized the construction company jointly owned by Imamugru Construction, Trade and Industry and handed over control to the court.

Most of the 105 people arrested by Istanbul Municipal Government staff along with Imamogru.