Under UK legislation (CDG 2009 / IRR17), within what timeframe must a serious radioactive transport incident (such as package breach or theft) be reported to the Office for Nuclear Regulation (ONR)?

1. Within 6 months by second-class post
2. Only after the vehicle is sold
3. No notification to ONR is required
4. Immediately by telephone / fastest available means, followed by a formal written report within 14 days