[DaRk_RaiN]

Pu this at the bottom of your script

pawn Код:

IsPlayerInArea(playerid, Float:MinX, Float:MinY, Float:MaxX, Float:MaxY)
{
    new Float:X, Float:Y, Float:Z;

    GetPlayerPos(playerid, X, Y, Z);
    if(X >= MinX && X <= MaxX && Y >= MinY && Y <= MaxY) {
        return 1;
    }
    return 0;
}

Now get the coordination of that area there are a lot of tutorials for that, after you get done with that use
OnPlayerUpdate to check if he is in the area
Put this in a timer or in OnplayerUpdate.

pawn Код:

if(IsPlayerInArea(playerid,MaxX,MaxY,MinX,MinY)&& !=IsPlayerAdmin(playerid))//change the MaxX,MaxY,MinX,MinY to the real cords
    {//This will only allow Rcon admin to get into the area, if you have an admin system, change IsPlayerAdmin
    SetPlayerHealth(playerid,0);//Kills the player
    SendClientMessage(playerid,-1,"this area is only for admins);//bla bla
    return 1;
    }