This is a frequent, and annoying bug on SAMP..... i was happy to NOT see it in MTA.. but ....well..
This is easily reproduced when someone does a behind the back stealth kill with the knife and their player animation does the death sequence.. it never recovers from the death on your client. So even tho they think they are walking around, your client sees them in their death position.
This is a little different on MTA it seems, as it looks more like the player is stretched out here. But perhaps a similar problem.