YORK's first partially electric buses have been launched as part of the drive to reduce pollution on the city's streets.

Five Hybrid Electric Vehicles (HEVs) are being put into service on the Number 4 route, which runs between Acomb and the University of York via the city centre.

Operator First said the state-of-the-art buses are powered by a combination of batteries and conventional diesel.

"The new technology produces 30 per cent lower carbon emissions compared to a conventional diesel bus," said a spokesman. " As well as being kinder to the local environment, the hybrid vehicles are also quieter than conventional buses."

The hybrids have arrived just weeks before six brand new electric buses are launched in June.

Cllr David Levene, Cabinet Member for Transport at City of York Council, said the arrival of the hybrids demonstrated how York's bus fleet could be transformed and the environment improved for the future, adding:"Our aim is to encourage more people to travel by bus and increase passenger numbers by 18 per cent by 2015."