A 4.0-magnitude earthquake shook Italy's volcanic region of Campi Flegrei west of Naples Monday, the latest in a series of tremors in recent days, officials said.

The quake, which occurred shortly after 10 pm (2000 GMT), did not result in any injuries or damage, the civil protection agency said on X, formerly Twitter, although it did cause panic among residents who spilled out into the streets.

The epicentre was located at a depth of around three kilometres (nearly two miles) between Naples and Pozzuoli, according to the National Institute of Geophysics and Volcanology (INGV).

The area around the Campi Flegrei (Phlegraean Fields) volcano, which last erupted in 1538 and would put half a million inhabitants in danger in the event of an eruption, has been the scene of increased seismic activity in recent days with a series of tremors.

On Wednesday, a 4.2-magnitude quake was recorded, the strongest the area has seen in 40 years.

INGV director Mario Di Vito warned that "it is possible that there will be tremors of greater intensity" in the near future.