There must be another condition in your mission,reason for killing all East-units.
Would be little weird to kill all eastunits from the start heh
Give that condition a Boolean (say Mycond = false)in the init.
Let this Boolean be true if you want to eliminate all eastunits.
Loop your "kiled.sqs",and use the:
@Mycond
line.
The script will exec when Mycond = true
Dont forget to switch Mycond to false at the end before U loop back to start.