Boy went missing from family home on Monday night in the wilderness of the Appenines.

A search continued throughout the night in a desperate attempt to find a toddler who went missing from his parents' house in a remote mountainous area in the Mugello region of northern Tuscany.

The 21-month-old Nicola Tanturli disappeared on the night between 21 and 22 June from a farmhouse in the Apennines where he lives with his German parents and four-year-old brother.

Authorities are currently working on the theory that the child woke up in the middle of the night, left the house - possibly while sleepwalking - and never returned.

Yesterday divers searched a nearby artificial lake but found no trace of the toddler while last night a helicopter with state-of-the-art thermal scanning and infrared equipment was deployed by the army and alpine rescue experts.

The search extends over an inaccessible area of about 10 square kilometres, involving around 200 people including carabinieri, mountain rescue and civil protection volunteers, in addition to drones and specially-trained dogs attempting to track the boy's scent.

Nicola's house, where his family runs a bee-keeping business, is reachable only by a dirt track, and the boy is described as very active and independent in his movements in the vicinity.

On Monday evening his parents put their two sons to bed but discovered Nicola's cot empty on Tuesday morning. After searching the house and surrounding land they raised the alarm and the carabinieri became involved.

The family home is located two kilometres from the Campanara ecovillage, a community of Italians and foreigners that has been practicing organic farming for decades.

In 1984 a group of like-minded people returned from travels in India and moved into abandoned buildings in the remote area where they lead a simple, environmentally-friendly way of life.