Lephalale – A truck and a bus were torched in violent a protest in Marapong outside Lephalale, Limpopo, on Thursday afternoon, police said.It is unclear whether the protest was related to a National Union of Mineworkers (NUM) strike at a nearby Exxaro coal mine, Limpopo police spokesperson Colonel Moatshe Ngoepe told News24.When police arrived at the scene they found a large gathering of people and the burning truck and bus barricading the road and "reacted swiftly to restore order to the area". Ngoepe said the vehicles burnt out completely.He said during the "unlawfulness" police were unable to determine the grievances of the protestors.No arrests have been made."We would like to call for calm from community members and ask them to go through the necessary processes to raise their concerns without using violence."NUM embarked on protests at the Exxaro mine on Thursday morning after the union failed to reach a wage increase agreement with the employer through the Commission for Conciliation, Mediation and Arbitration on September 6.In a statement, NUM spokesperson William Mabapa said Exxaro was served a 48-hour strike notice on Tuesday."The union demands a wage increase of 10%, service increment of 0.5% that is given to other employees and denied to other employees, housing increase of 10% or R5000.00, standby allowance of 10% [and] family responsibility leave of eight days,” Mabapa said.