Supporters of the vice-president have been gathering in the streets surrounding her home since last week, when a prosecutor called for a 12-year sentence for Kirchner as well as a lifelong prohibition in holding public office as part of a case involving alleged corruption in public works during her 2007-2015 presidency.

Kirchner, who is not related to the current president, has denied all charges.

The president spoke shortly after video from the scene broadcast on local television channels showed Kirchner exiting her vehicle surrounded by supporters outside her home when a man could be seen extending his hand with what looked like a pistol.

The vice-president ducked as supporters surrounding the person appeared shocked at what was happening amid the commotion in the Recoleta neighbourhood of Argentina’s capital.

The man, whose identity was not released by authorities, was detained seconds into the incident.

The president said the firearm had five bullets “and didn’t fire even though the trigger was pulled”.

There was no indication that the vice-president suffered any harm.

“A person who was identified by those who were close to him who had a gun was detained by (the vice-president’s) security personnel,” Security Minister Anibal Fernandez told local cable news channel C5N.

The minister said he wanted to be careful in providing details until the investigation learned more.

Unverified video posted on social media shows the pistol almost touched Fernández’s face.

State-run news agency Télam identified the alleged gunman as Fernando Andres Zabak, a Brazilian citizen. Officials had not confirmed the information.

Government officials were quick to describe the incident as an assassination attempt.

“When hate and violence are imposed over the debate of ideas, societies are destroyed and generate situations like the one seen today: an assassination attempt,” Economy Minister Sergio Massa said.

Ministers in President Alberto Fernandez’s government issued a news release saying they “energetically condemn the attempted homicide” of the vice-president. “What happened tonight is of extreme gravity and threatens democracy, institutions and the rule of law,” reads the release.

Former president Mauricio Macri also repudiated the attack. “This very serious event demands an immediate and profound clarification by the judiciary and security forces,” Macri wrote on Twitter.

Patricia Bullrich, president of the opposition Republican Proposal party, criticised the president, saying he is “playing with fire” because “instead of seriously investigating a serious incident, he accuses the opposition and the press, decreeing a national holiday to mobilise activists”.

Tensions have been running high in the upper class Recoleta neighbourhood since the weekend, when the vice-president’s supporters clashed with police in the streets surrounding her flat amid an effort by law enforcement officers to clear the area.

Following the clashes what had been a strong police presence around the vice-president’s home was reduced.

When Kirchner leaves her home every day at around noon, she greets supporters and signs autographs before getting in her vehicle to go to the Senate. She repeats the same routine every evening.

Following the incident, allies of the vice-president quickly pointed the finger at the opposition for what they say is hateful speech that promotes violence. In recent days, several key officials have said opposition leaders were looking for a fatality.

“This is a historic event in Argentina that must be a before-and-after,” Buenos Aires Governor Axel Kicillof said.

Regional leaders also condemned the attack.

“We send our solidarity to the vice-president in this attempt against her life,” Venezuela’s President Nicolas Maduro said on Twitter.

Former Brazilian President Luiz Inacio Lula da Silva, who is a candidate in that nation’s presidential election next month, also expressed solidarity with Kirchner, calling her a “victim of a fascist criminal who doesn’t know how to respect differences and diversity”.