Nil value on SGroup_IsUnderAttack and Entity_Kill()

SCAR ERROR Callstack: 

   Lua             city_centre_2.scar"]           Ln  438 (_BonusObjective_Civs_Timer)

23:32:53.48   GameObj:nFatalScarError: [[string "DATAcenarios\city_centre_2.scar"]:438: attempt to call global 'Entity_kill' (a nil value)]

function _BonusObjective_Civs_Init()



    -- Start civilian rescue bonus objective

    Objective_Start(OBJ_Bonus_Civilians)



    -- Set up up encounters

    Rule_AddDelayedInterval(BONUS_CIVS_Encounters_Init, 1.5, 1)

end



function BONUS_CIVS_Encounters_Init()



    if Objective_IsStarted(OBJ_Bonus_Civilians) then

        Rule_RemoveMe()

        

        --World_IncreaseInteractionStage()

        

        sg_bonus_civs_e_all = SGroup_CreateIfNotFound("sg_bonus_civs_e_all")

        

        BONUS_CIVS_Enemy_01()

        BONUS_CIVS_Enemy_02()

        

        EGroup_SetSelectable(eg_bonus_civs_building, true)

        

        -- Spawn the units

        sg_bonus_civs_a_all = SGroup_CreateIfNotFound("sg_bonus_civs_a_all")

        

        Util_CreateSquads(player3, sg_bonus_civs_a_all, SBP.SOVIET.BASE_CONSCRIPT_SQUAD, eg_bonus_civs_building)

        Util_CreateSquads(player3, sg_bonus_civs_a_all, SBP.SOVIET.BASE_CONSCRIPT_SQUAD, eg_bonus_civs_building)

        --Util_CreateSquads(player3, sg_bonus_civs_a_all, SBP.SOVIET.BASE_CONSCRIPT_SQUAD, eg_bonus_civs_building)

        

        Modify_WeaponDamage(sg_bonus_civs_a_all, "hardpoint_01", 0)

        

        EGroup_EnableUIDecorator(eg_bonus_civs_building, false)

        

        SGroup_SetInvulnerable(sg_bonus_civs_a_all, true)

        

        --Event_GroupLeftAlive(_Bonus_Civs_Retreat_Enemies, nil, sg_bonus_civs_e_all, 3)

    end

end



function _BonusObjective_Civs_Timer()

    -- Check if both enemy groups are dead

    if SGroup_TotalMembersCount(sg_bonus_civs_e_01) <= 0 and SGroup_TotalMembersCount(sg_bonus_civs_e_02) <= 0 then

        Rule_RemoveMe()

        return

    end



    -- first check to see if the timer is active

    if Timer_Exists(tmr_bonus) then



        -- Check the remaining time and check if any civilians have been under attack within the next 3 seconds

        if Timer_GetRemaining(tmr_bonus) <= 0 then

            

            -- -- select a random civlian squad 

            local sid = SGroup_GetRandomSpawnedSquad(sg_bonus_civs_a_all)



            -- count remaining civilians in chosen squad 

            local count = Squad_Count(sid)



            -- returns a random integer between 1 and the remaining civilians in the chosen squad

            local index = World_GetRand(1, count)



            -- select the random integer of civilians minus 1 to kill

            local eid = Squad_EntityAt(sid, (index-1))



            -- kill selected civilians from randomly chosen civilian squad

            Entity_kill(eid)



            --SGroup_Kill(sid)





            -- Update the Objective_SetCounter

            Objective_SetCounter(OBJ_Bonus_Civs_Loss, SGroup_TotalMembersCount(sg_bonus_civs_a_all))



            Timer_End(tmr_bonus)

        end    



    -- Rule if the timer is inactive

    elseif Timer_Exists(tmr_bonus) == false then



 -- check if all civilians are dead 

        if SGroup_TotalMembersCount(sg_bonus_civs_a_all) <= 0 then

            Rule_RemoveMe()

            Rule_Remove(_BonusObjective_Civs_Rescued)



            -- enemies are victorious. They retreat back to the city centre

            -- Cmd_Retreat(sg_bonus_civs_e_01, mkr_bonus_civs_e_retreat, mkr_bonus_civs_e_retreat)

            -- Cmd_Retreat(sg_bonus_civs_e_02, mkr_bonus_civs_e_retreat, mkr_bonus_civs_e_retreat)



            -- all civilians are dead, the objective is failed

            Objective_Fail(OBJ_Bonus_Civilians)

            return

        end



        -- restart the timer 

        Timer_Start(tmr_bonus, t_difficulty.death_rate)



    end



end

attempt to call global 'Entity_kill' (a nil value)