Volcanic area registers increased seismic activity in recent days.

Italy's volcanic Campi Flegrei or Phlegraean Fields area near Naples was shaken by a 4.0-magnitude earthquake on Monday night, the latest in a series of recent tremors.

The epicentre of the quake was located at a depth of about three kilometres, between Naples and Pozzuoli, according to Italy's National Geophysics and Volcanology Institute (INGV).

The earthquake, which struck just after 22.00 and was felt clearly in Naples, sent people running out of their homes in panic however there were no reports of injuries.

[DATI #RIVISTI] #terremoto Md 4 ore 22:08 IT del 02-10-2023 a Campi Flegrei Prof= 2.6 Km #INGV_36365741 https://t.co/QdKl19wdeD— INGVterremoti (@INGVterremoti) October 2, 2023

Plaster fell off buildings in Agnano where many people spent the night on the street, news agency ANSA reports, as civil protection authorities and firefighters continued to carry out structural checks in the area on Tuesday.

"It was a shallow earthquake, people felt it strongly especially in the Agnano area, closer to the epicentre", the director of the Vesuvius Observatory, Mauro Di Vito, told television station Canale 21 - "The seismic activity continues and will continue. There is no doubt about this."

#Terremoto, crollo di calcinacci ad #Agnano. Gente per strada in diverse zone di #Napoli, a #Pozzuoli e intera area flegrea magnitudo 4 #CampiFlegrei @TgrRai @TgrRaiCampania #IoSeguoTgr pic.twitter.com/xedxeisemg— Antonello Perillo (@anperillo) October 2, 2023

Declared a regional park 20 years ago, the Phlegraean Fields area is a highly seismic zone of supervolcanic calderas, situated to the west of Naples.

Last Wednesday the area registered a 4.2-magnitude earthquake, the strongest in 40 years, raising fears of a volcanic eruption among the roughly half a million residents in the so-called 'red zone' most at risk.

The Campo Flegrei volcano last erupted in 1538 however earthquakes have been common in the area since 1950, with a surge of seismic activity in the early 1980s.

Italy's civil protection minister Nello Musumeci said last week that authorities are drawing up an evacuation plan for Campi Flegrei in the event of an emergency, however he cautioned against "alarmism".