Venice police investigating bright green liquid in Grand Canal

Police in Venice have launched an investigation into the source of a phosphorescent green liquid patch that has appeared in the city's famed Grand Canal.

Luca Zaia, governor of the Veneto region, posted a picture of the bright green liquid near the arched Rialto Bridge on Sunday.

The patch was reported by residents.

Images taken at the scene show a bright patch of green in the canal along an embankment lined with restaurants.

Mr Zaia said that officials had requested that the Venice police investigate to determine who was responsible.

Environmental authorities have also been testing the water.

The incident appears to echo recent episodes in Italy in which environmental groups have been targeting monuments with colours and dyes.

Previous incidents include activists using vegetable charcoal to turn the waters of Rome's Trevi fountain black in a protest against fossil fuels.

However, unlike previous cases, no protest group has come forward yet to claim responsibility for what happened in Venice.