Light aircraft down near Steyning, West Sussex
 

Info from AAIB.

Media reporting forced landing after EF, two on board, both seriously injured.

Air ambulance was returning to Redhill from a task near Brighton and was on scene within a few minutes. Hope both POB are already on the road to a good recovery.

Loks like a twin, Seneca type perhaps?

Reg number comes up as a Cherokee 6

The colours match to G-KNOW. Perhaps the engine was detached on impact and gives the appearance of a twin?

Definitely Lydd-based G-KNOW PA-32 Cherokee Six (single-engined).