Plugin conflict.
https://forums.alliedmods.net/showthread.php?t=318965
Tanks sometimes throw rocks [Tesla][Medic][Firework].
It seems to be random, sometimes normal, sometimes these situations occur.
If there is a conflict, all the items on the map will disappear.
The server will explode ping. The player is all dropped. Some clients will crash.
But the server won't crash.