Protocol: Stop, Secure, Call
Three steps after an accident: 1) Stop immediately, turn on hazard lights. 2) Place the warning triangle 50–100 metres behind on an urban road, 100–150 metres on a country road, further on a motorway. 3) Call 112 for injury, fire, blocked road or suspected drunk driving. Trafikbrottslagen §5 requires you to stop and provide details — name, address, insurance — even if the other party doesn't ask.