Motorists have been cautioned to plan their trips along the N3 toll concession road after reports that at least four trucks were burnt in KwaZulu-Natal overnight.Officials confirmed at least four heavy goods vehicles were torched in the vicinity of Mooi River, Frere and Pietermaritzburg on Saturday night and into Sunday morning, East Coast Radio reported."In the light of recent disruptive protests, incidents of criminality and attempts to obstruct the free flow of traffic on some of our country's major transport networks, including the N3 toll route, N3 toll concession (N3TC) strongly advises road users to avoid night time travel, if at all possible. "It is advisable to rather plan long distance trips during daylight hours," said N3TC's commercial manager Con Roux in a statement on Sunday.Freeways within the N3TC's authority have since been cleared on Sunday - between Cedara in KwaZulu-Natal and Heidelberg in Gauteng. Other traffic around Pietermaritzburg towards Gauteng had been affected.Roux said that disruptive actions aimed at the trucking industry were often "opportunistic and unpredictable and mostly occur under the cover of darkness". It was also not limited to a specific area, location or route. Motorists taking that route were advised to contact the N3TC's 24-hour helpline on 0800 63 4357 before embarking, and were requested to report suspicious behaviour to the same number.KwaZulu-Natal police were collating information on the various incidents around the province at the time of writing. This article will be updated upon receipt of the information."South Africa's road network forms the backbone of our economy. All support to help us ensure that our roads remain as safe as possible is appreciated," Roux added. (Images supplied)Elsewhere in the country, a 50-year-old truck driver suffered serious burn wounds after his truck was petrol bombed along the N1 roughly 10km outside of Touws River in the Western Cape.READ: Truck driver suffers serious burn wounds after N1 petrol bombingHe and his brother was treated by paramedics on scene and later rushed to Mediclinic Worcester for further care. Western Cape police confirmed that cases of attempted murder and malicious damage to property were opened for investigation. No arrests have been made.