Cape Town - A series of "senseless assaults" on Metrorail staff, train hijackings and other attacks between Mamelodi and Pretoria was slammed on Wednesday by transport minister Blade Nzimande, who described it as "despicable".In the most recent incident, a female train driver was assaulted and the train was stoned between Pienaarspoort and Pretoria on Tuesday.More than 10 employees were attacked in less than a week and more than six trains have been withdrawn from service, the Department of Transport said in a statement.Spokesperson Ishmael Mnisi said it was unclear what the reason for the series of attacks was.READ: 'Prasa is under siege' - acting CEO on latest Cape Town rail attackNzimande was "extremely concerned" about the impact on commuters who rely on trains to travel between work and home."These despicable acts cannot be allowed in our democracy, where individuals with underhand motives undermine government efforts and commitment to modernise rail services in our country. We will not allow anyone to turn our rail network into a fertile ground for criminality."These acts of deliberate destruction are condemned and law enforcement agencies will continue to work hard to arrest all the perpetrators of this senseless destruction of property, criminality and sabotage."He said Prasa would investigate the nature, extent and severity of "these recent acts of contempt"."I have already begun engagements with stakeholders and concerned citizens on the challenges that are facing Prasa. Over and above that, together with the relevant provincial MECs, I will convene a gathering of key stakeholders as a matter of urgency, thoroughly to engage on this matter, and come up with concrete proposals on how to deal with this situation at once. The Minister of Police will also be part of these engagements," Nzimande said. IN DEPTH: Inside Metrorail’s cable theft and commuter crisisThe Railway Safety Regulator on Wednesday said no train hijackings had been reported to them."It is the responsibility of operators to report railway occurrences and incidents to the RSR," it said in a statement.The last reported incident according to the regulator, was in January 2012.