please look at these video evidence

I can't record from first person perspective since this game server doesn't have spectator slots but I think these clips are obvious

https://youtu.be/vEspafEs6Kw?t=291

https://youtu.be/vEspafEs6Kw?t=488

https://youtu.be/vEspafEs6Kw?t=515

https://youtu.be/vEspafEs6Kw?t=551

https://youtu.be/vEspafEs6Kw?t=832

https://youtu.be/vEspafEs6Kw?t=870

these clips are suspicious scenes of following two games

http://battlelog.battlefield.com/bf4/battlereport/show/1/1027183104202452864/1573603129/

http://battlelog.battlefield.com/bf4/battlereport/show/1/1027185733179617152/1573603129/

And I found a lot of suspicious battlelog reports (very high K/D)

http://battlelog.battlefield.com/bf4/battlereport/show/1/1027213224164288064/913920923

http://battlelog.battlefield.com/bf4/battlereport/show/1/1034874557728312896/913920923

http://battlelog.battlefield.com/bf4/battlereport/show/1/1034171398033392000/913920923

http://battlelog.battlefield.com/bf4/battlereport/show/1/1034106220029925696/913920923/ (Including 7 kills with railgun) 

https://bf4db.com/forum/thread/santu-sanchez-is-not-clean-3859