Visitors have taken to social media to express their shock at the scenes unfolding in the city.
One person simply tweeted: “Vatican on fire”.
Another said: “Possible explosion at the Vatican.”
A third posted online: “Currently a major fire (near the #Vatican), heavy smoke, big column of smoke rises up into the sky.”
According to reports the Pope is inside the Vatican.
Alarming footage from the scene shows black smoke pouring into the sky at a considerable rate.
One eyewitness said they saw smoke, adding: “Then a few minutes later there was a loud boom and more smoke”.
“I’ve heard lots of sirens.
“The smoke was drifting high over my apartment.”
Photos show a fire raging in a building.
This is a developing story.
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