Angry reactions appeared on Twitter with the hashtag #لا لحبس الصحفيين, or "No to the imprisonment of journalists," with various political groups issuing statements condemning the decision.

Well-known activist Wael Ghoneim declared on Twitter: "An eternal Egyptian saying... Courts coddle rulers." He went on to say that journalists who print false information should be forced to publish retractions and pay fines if they repeated the mistake.  

Ghoneim added that the charge of "insulting the president" could be easily politicised.

"Someone can write his personal opinion that the president is weak and unable to make decisions, and consequently be tried on charges of insulting the president," he said.

According to Article 179 of Egypt's Press Law, "whoever affronts the president of the republic" can be subject to detention.

"Al-Dostour's editor-in-chief violated the ethics of the profession and readers' trust, but jailing people for expressing their opinions is a way of muzzling critics," said prominent journalist Hamdi Qandil. He went on to call for the creation of a 'Media Council' to arbitrate in such cases.

Some political activists contrasted Afify's detention with the light sentences given to security personnel found guilty of killing anti-regime protesters. "Police officers accused of killing protesters were acquitted, while those who make the president angry must be put in jail right away," said one activist.

Former Arab League chief and presidential candidate Amr Moussa, for his part, said: "The real offence for any political regime is to begin its ruling period by detaining journalists in opinion cases."  

Another activist tweeted: "People wanted freedom, now they're stuck with freedom and justice," in a reference to the Muslim Brotherhood's Freedom and Justice Party (FJP).

Another chimed in: "Today they're putting journalists on trial; next they'll be trying people [who express their opinions] on Facebook and Twitter. Eventually, no one in the country will dare say anything."

Reform campaigner and Constitution Party founder Mohamed ElBaradei, for his part, declared via Twitter: "Inciting murder in the name of religion and accusing revolutionaries of treason are not crimes, while insulting the president in the press is a crime that deserves detention! It's as if there was no revolution."

The leftist Tagammu Party, meanwhile, declared its solidarity with journalists put on trial for insulting the president. In a statement, the party said that the move was intended to "terrorise journalists" and represented an "assault" on press freedom.

A number of Egyptian intellectuals are planning to stage a demonstration on Thursday in downtown Cairo's Talaat Harb Square to protest the move.

Veteran Nasserist and former presidential candidate Hamdeen Sabbahi has voiced support for Thursday's protest. In a statement, Sabbahi described press freedom as "one of the main bases of democracy," stressing that it was "no longer acceptable" to attempt to curb press freedoms after last year's revolution.

In the meantime, Afify has been transferred to Cairo's Tora Prison. Newly-appointed Vice President Mahmoud Mekky, for his part, has been quoted as saying that President Morsi was looking for a legal way out for Afify without interfering in judicial decisions.

Mekky told Egypt's Al-Badeel newspaper that Mosri was considering using his legislative authority to overturn any Mubarak-era laws that call for imprisonment for so-called "publishing offences."

On Thursday evening, Egyptian state news agency MENA reported that the president had issued a law cancelling the practice of detaining journalists for press offences, meaning that Afify would likely be released.

A Constitutional Declaration issued by Morsi earlier this month gave the president full legislative powers, which he will command until the election of a new parliament.