South Africa has a high record of carjacking when compared with other industrialised countries. Insurance company Hollard Insurance stated in 2007 that they would no longer insure Volkswagen Citi Golfs, as they were one of the country's most frequently carjacked vehicles. Certain high-risk areas are marked with road signs indicating a high incidence of carjackings within the locality. Smash-and-grab robbers or opportunist vagrants target slow-moving traffic in cities, cars at filling stations or motorists that have become stranded beside highways. More brazen robbers may resort to throwing rocks, petrol bombs or wet cement at vehicles to bring them to a standstill, or may drop rocks from overpasses. Various debris like concrete slabs, tyres or rocks are also placed on roadways, or a car may be tapped or bumped to induce the driver to leave the vehicle. So-called "blue light gangs" have been active in Gauteng since 2018, who employ vehicles fitted with blue lights and sirens, and wear police apparel to convince motorists or truckers to cooperate.