No injuries or damage in incident.

A large pine tree in Rome's central Piazza Venezia fell on Thursday, crashing to the ground into Piazza S. Marco after its roots gave way.

Despite the busy location in front of the Altare della Patria monument there were no injuries or damage, with the tree falling parallel to the pavement in Piazza S. Marco at around 07.30.

The city's environment department is carrying out an investigation into the incident, with the effects of the current heatwave on the tree's roots cited as a possible cause for its collapse.

The pine, believed to be about 80 years old, was "pruned and underwent all the necessary treatments, including traction tests, three years ago", said Rome's mayor Roberto Gualtieri who visited the site on Thursday morning.

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"It appeared to be in excellent shape, it was solid" - Gualtieri told state broadcaster RAI News - "It was a well-kept tree. But seeing it now, it would seem that a sort of 'cavity' had formed inside."

However the mayor stressed that this was "only a hypothesis" and suggested that the tree's stability may have been comprised after its roots were cut back during roadworks in the past.

Stefano Marin, chairman of the environment committee in the city's Municipio 1 borough, said the incident called for "a moment of reflection".

"Rome's trees are of a certain age and climate change is already producing effects" - Marin told La Repubblica newspaper - "Rome is once again filled with tourists, it's both an environmental and a safety issue."

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The incident occurred as works get underway for the construction of the Piazza Venezia subway station for the Metro C underground line.

In recent years the city's pines have been decimated by a sap-eating parasite called the pine tortoise scale or toumeyella parvicornis.

Treatment programmes to combat the bugs are underway around Rome however authorities have been accused of acting too late or not at all.

The deadly effects of the insect are now plain to see on swathes of Roman pines, whose foliage has a burnt or threadbare appearance, posing a serious threat to the city's iconic skyline.