Turkey vowed to root out allies of the US -based cleric it blames for an abortive coup last week, widening a purge of the army, police and judiciary on Tuesday to the education sector, intelligence agency and religious authorities.

He has accused followers of his arch-enemy, US-based cleric Fethullah Gulen of being behind the coup, which has led to a wave of some 50,000 arrests and sackings of suspected conspirators.

Bulent Gedikli, chief adviser to Erdogan, said suspended civil servants would be immediately replaced. Among them are 1,577 university deans, who have been asked to resign in addition to 21,000 teachers and 15,000 education ministry officials.

"In a country where our youths are killed with tanks and bombs, if we stay silent, as political people we will be held responsible in the afterlife", Erdogan said, pointing out that capital punishment exists around the world, including in the United States and China.

Interestingly, so did the AK Party's opposition, as did President Erdogan's supporters, who flocked to the streets to show their support when he returned to Istanbul in a last-minute press conference.

On Tuesday, US President Barack Obama said he was "willing to provide appropriate assistance to Turkish authorities investigating the attempted coup", according to his spokesman, Josh Earnest.

In parallel talks, U.S. Defense Secretary Ash Carter and his Turkish counterpart discussed the importance of Turkey's Incirlik Air Base in the campaign against Islamic State in Syria and Iraq, the Pentagon said.

Turkish President Tayyip Erdogan speaks during a news conference following the National Security Council and cabinet meetings at the Presidential Palace in Ankara, Turkey, July 20.

For his part, Gulen says claims he was behind the coup attempt are "ridiculous".

Yet now, the suppression of the failed coup has only further exposed the levels of polarization that have given President Erdogan exceeding authority over his country and its constitution.

Any workers suspected of wrongdoing should undergo a formal investigation and the fight against coup plotters "should not be turned into a witch hunt", Ozev said.

Responding to the attempt on Saturday, Erdogan said it was "a gift from God" since it will give the government "a reason to cleanse our army".

The cleric, Fethullah Gulen, has denied all knowledge of the coup - and has suggested that President Recep Tayyip Erdogan's government could have staged the coup as a way of consolidating power and eliminating government opponents.

But the speed with which Turkey's Telecommunications Directorate, the state internet watchdog, blocked access to the site raises questions about what will be found in the archive once researchers have had a chance to examine it more thoroughly.

Officials on Wednesday raised the death toll from the violence surrounding the coup attempt to 240 government supporters.

Rights and freedoms in the country may also be limited or suspended if the government decides to do so, the news agency explained.

"In the upcoming days, politics in Turkey will focus on cleaning the state from members of the Gulen movement", Mis said.

Already, around 9,000 people including police and government officials have been sacked and at least 9,300 people detained including more than 100 generals and admirals accused of masterminding the plot.