yesterday morning in Battersea…right outside a train station…I actually heard it rather than saw ir - impact and lots of screaming - it was a few cars ahead…van coming out of a side entrance - seemed to take out bike and biker.
Passerby got to work and he soon had his leg wrapped up whilst we waited for an ambulance - impressed with those guys - literally five mins and they were on scene.
Moved his bike out of the road and retrieved his keys and topbox - all looked fairly fecked with plenty of debri - including the van bumper all over the road.
One query - good idea to move things - defo no way traffic was moving unless we did - or should you wait for the police?
Note to self for next time - wipe clean boots of oil / petrol or whatever I was standing in - feet very slippers on bike as I carried on journey.
Had I been 30 secs ahead - would’ve been me…sobering thought.
Take photos. If you don’t move stuff, someone else will!
+1 photo’s are a good move… if it’s fatal (god forbid) don’t move anything… the traffic will have to wait!
Always take photos before moving anything.
Was knocked off myself once before & some1 had moved the bike before any pics were taken or police arrived on the scene.
When it came to the claim the 3rd parties insurance argued liability as there was no photographic evidence of the accident to back up the claim, resulting in taking over a year before i received any compensation 
thankfully I had Fully Comp & my bike was repaired otherwise i’d have been without a bike for all that time!!
Official stance on this is to wait for the Police before moving stuff if there is evidence of dangerous driving or a fatality/serious life changing injuries. Trafic will usually be brought in by the first police on scene, if they’re not already tasked to it. If it’s not a life threatening/changing injury, take photo’s if the vehicles are needed to be moved for safety etc… But generally I’d say let the Police decide, and let the traffic wait! 
