Erdogan appears to have used the coup attempt to further concentrate powers in his hands. The nationwide arrests and dismissals have unsettled a country that was already bitterly divided over what many describe as a yearslong effort by the Turkish leader to cripple his rivals and weaken counterbalancing institutions.
In the wake of the failed coup, he has suggested restoring capital punishment, which was abolished in 2004.
The statement earned a sharp rebuked from Austrian Foreign Minister Sebastian Kurz ahead of a meeting with fellow European Union ministers, who called it "absolutely unacceptable."
"There must be no arbitrary purges, no criminal sanctions outside the framework of the rule of law and the justice system," he said in newspaper interview published Monday.
The international community has strongly backed the Turkish government against the coup, but there has been some disquiet about the recent purges.
Federia Mogherini, the European Union's foreign policy chief, said Monday that the rule of law and system of check and balances must be respected in the coup's aftermath.
Arrest warrants have also been issued for at least 2,745 judges and prosecutors across the country, according to Turkish media reports.
The Turkish leader has alarmed many here with his attempts to consolidate power over the years. Some Turks have expressed concern that Erdogan will use the attempted coup to further marginalize all forms of challenge to his growing powers, whether peaceful or not, even as the country struggles with myriad crises.
Those include deep divisions over the role of Islam in Turkish politics, worsening unrest from within the large minority of Kurdish citizens and spillover from the civil war in neighboring Syria.
Turkey defense minister told supporters of Erdogan to stay in the streets for now, warning that the threat of the coup was not over.
"The coup was prevented, but we can't say the threat is gone," said Fikri Isik, according to the state-run Anadolu news agency. "We ask you to closely follow every statement of Mr. President and stay in the squares."