Italian authorities investigating 'aggravated threats' after Greta Thunberg effigy hung from noose

Italian authorities are investigating "aggravated threats" after an effigy of climate change activist Greta Thunberg was hung from a noose in Rome.

Photos posted to social media show the dummy dressed with long braids along with a sign written in English reading "Greta is your God".

"We hanged Greta Thunberg in Rome. The dummy has its face and even its braids. Other actions will follow," said the group which claimed responsibility, according to Italian newspaper la Repubblica

The effigy was removed from the bridge on Via Isacco Newton by Rome firefighters accompanied by police.

Rome mayor Virginia Raggi took to Twitter to denounce the act as "shameful". She expressed solidarity to the 16-year-old, along with the message "our climate commitment does not stop".

Leftist PD party leader Nicola Zingaretti also condemned the "grisly violence".

Thunberg has faced backlash around the world ever since she became the face of climate activism.

Last week Russian President Vladimir Putin took aim at the teen, telling an energy forum he did not share the excitement about her United Nations speech last month.

"No one has explained to Greta that the modern world is complex and different and ... people in Africa or in many Asian countries want to live at the same wealth level as in Sweden," he told an energy forum in Moscow.

Thunberg has also been mocked on Twitter by US President Donald Trump following her tearful performance at the UN by calling her a"very happy young girl".

Canadian Member of Parliament Maxime Bernier has also weighed in, labelling her alarmist and mentally unstable.

Despite this, Thunberg is tipped to win the 2019 Nobel Peace Prize.