ROME—Pope Francis on Thursday warned that journalism, when based on rumors, can be a form of terrorism, meaning a “weapon of destruction” of both people and nations.

The pontiff also urged journalists not to stoke fear regarding phenomena such as migration forced by war or hunger.

“I have often spoken of rumors as ‘terrorism,’ of how you can kill a person with the tongue,” Francis said.

“If this is valid for an individual person, in the family or at work, so much more it’s valid for journalists, because their voice can reach everyone, and this is a very powerful weapon,” he said.

Criticism, the pope continued, is legitimate, as well as the “denunciation of evil, but this must always be done respecting the other, his life, his affections,” because an article is replaced from one day to the other, but the life of a person “unjustly defamed can be destroyed forever.”

Francis’s words came on Thursday, as he was addressing close to 400 journalists from the Italian National Council of the Order of Journalists. After his remarks, he took the time to greet each one of them.

The pontiff also said that when practiced with professionalism, journalism is a fundamental element of an independent and pluralist society.

To make sure it’s lived as such, Francis offered a reflection on three aspects of the profession: love for the truth, living with professionalism, and respect for human dignity. He spoke about the danger of journalists becoming terrorists by publishing rumors or spreading fear.

On the first, the pope said that it’s not about believing in something or not, but about being honest, and never publishing a story – either in print, radio, TV or social media- knowing it’s false.

“I understand that in today’s journalism, with an uninterrupted flux of facts and events told 24 hours a day, 7 days a week, it’s not always easy to get to the truth, or even to get close to it,” Francis said.

Using a concept he’s used before when talking to priests, he also said that not everything in life is black or white.

“Even in journalism, it’s necessary to discern between the shades of gray of the events being told,” he said, particularly when it’s about topics such as politics or war, that are rarely the result of clear dynamics.

Living with professionalism, according to Francis, means not to pin one’s profession to the interests of others, either economic or political.

“It’s important to always reflect on the fact that, across history, dictatorships- of any orientation or ‘color’- have always tried to not only undertake the media, but also to impose new rules to the profession,” he said.

Closing his remarks, he called journalists to be an “instrument of construction,” factors in the common good, capable of avoiding the temptation of fomenting confrontation and instead promoters of a “culture of encounter.”