After a traffic accident, you should not normally move any vehicles if someone has been injured or died in the accident, as it can make an investigation of the accident more difficult.
However, if there are vehicles on the road that pose a danger or an obstacle to traffic, they should, if possible, be moved to a safer place – even if severely injured persons are inside.
Normally, you should not move injured persons either. But if a person is at risk of being run over or being exposed to fire, or if it is required for you to be able to perform first aid, you should move the person.