Tokyo - Images of the third generation Toyota Prius have been revealed on the internet months prior to the official debut at the Detroit Motor Show in January 2009, showing minor design modifications such as a more aggressive looking bonnet with a centrally positioned nose cone.

Most of the changes are technical with Toyota confirming on its blog site that the images are real and that further details will be revealed in Detroit.

Germany's auto-motor-sport magazine, however, reports that the new model will be available in an Eco and Executive versions with more comfort features. The range in electric mode is four kilometres with carbon dioxide emissions reduced from the current 104 grams per kilometre to 92 g/km. The Eco version is said to achieve some 89 g/km.

The 2009 model is still fitted with the old nickel-metal hydride (Ni-MH) battery pack but Toyota is planning a plug-in hybrid with lithium-ion batteries for 2010. Initially it will be reserved for fleets and made available to private customers 2012 with an electric-mode range target of 13 kilometres.

First introduced in 1997, the Toyota Prius is still one of the lowest emission vehicles on the road. It was again chosen as the cleanest vehicle on the road by Germany's automobile association ADAC this year. (dpa)