Bus operator Arriva has admitted a defect in a number of the new buses’ fuel caps was to blame for diesel leaking onto the roads.

Around 30 buses were found to have the defect and the problem had been rectified, a spokesman for the operator said.

The Civil Protection Department was forced to intervene several times to deposit sand on the roads to prevent accidents.

Sources close to the CPD said most of the calls received for intervention were made in the morning, soon after the Arriva buses left their garages to fill up their tanks for the day. Moreover, most of the incidents were reported around roundabouts or sharp corners.

Police sources said no incidents involving diesel spilled by Arriva buses had been reported.

When contacted, a spokesman for Arriva confirmed the company “had experienced some problems with fuel caps on a small number of the bus fleet”.

She added that modifications had subsequently been made to rectify the problem. Arriva’s environmentally-friendly buses were bought from China. Arriva’s bus service has been riddled with problems since the company took over the public transport system on July 3.