Officers are patrolling city buses after 'mindless' vandals have hurled bricks and stones at the vehicles over the recent weeks in the Earlham area.

Three incidents have been reported over the last month as objects have been thrown at moving vehicles, causing 'distress' to passengers.

A spokesman for Norfolk Police said: 'Buses in the Earlham area have been damaged by persons throwing stones etc. at them whilst they are in transit causing damage to the windows and distress to the passengers.'

The first came around 8.45pm on September 5 when a brick was hurled through the window of a service while travelling along Earlham Road.

Then on Winchcomb Road on September 13 at 7pm, and September 14 at 8pm, stones were thrown at buses, smashing side windows in the process.

There is not believed to have been any injuries.

Chris Speed, head of operations for First Eastern Counties said: 'We have encountered a number of incidents over the past month, whereby objects have been thrown at buses causing damage to the bodywork and windows.

'The events seem to be happening in the evening and thankfully we have not experienced any injuries to passengers.

'The safety and wellbeing of our customers and staff is paramount and we are assisting the Police in apprehending the culprits and will prosecute anyone that is involved in this criminal activity.

'It is a mindless act and also a costly exercise for us to replace windows and repair damaged bodywork on buses that are affected.

Police have promised to 'deal robustly' with the offenders and are reviewing CCTV.

In a series of tweets, Norwich Police said: 'Throwing objects at moving vehicles is dangerous.

'We are conducting patrols on buses and reviewing CCTV to identify suspects.

'If identified, offenders will be dealt with robustly.'

Sgt Mark Shepherd, community sergeant for Norwich East and Safer Neighbourhood Team, has also appealed for information to help stop the 'dangerous behaviour'.

Anyone with any information about the offences should contact PC Wickham on non-emergency number 101.