An explosion under a public road at 10 am raised 20 m² of road (30 cm thick). A safety perimeter was set up. The occupants of nearby buildings stayed inside and the traffic was stopped during the time needed for the firefighters, and electricity, gas and telecommunications utilities to identify the cause of the accident: the explosion occurred when a 225 kV underground electric cable, isolated by pressurised oil in a pipe line, was switched back on. Valves were closed to isolate the section affected. The metal shell no doubt broke suddenly, creating a crater of several meters in diameter in the roadway. 4 people received minor injuries from the blast, 2 vehicles were damaged and 1,000 L of oil were spread over the ground. The line was automatically switched off. An external company carried out road works within the next few hours and a 2nd company drained and collected the dielectric oil. The emergency response phase ended at around 4 pm. The town’s 225 kV power grid was momentarily weakened, but users suffered no power cuts.