What is causing Unknown field error in EntityFieldQuery API? I am attempting to use the entity-field-query API to see if any node of referee content type has custom field that equals x. I've looked at dozens of code examples and references. (Included below)

If it is relevant I am executing this code as a custom PHP action in Drupal rules.

My problem is when the code is executed I get the below error: 

EntityFieldQueryException: Unknown field: field_referee_id‎ in EntityFieldQuery-&gt;addFieldCon
dition() (line 817 of /home/scienceorg/public_html/includes/entity.inc).


(The field does exist on the referee content type.)

My code:

&lt;?php
error_reporting(E_ALL);

$query = new EntityFieldQuery();
    $query
    -&gt;entityCondition('entity_type', 'node')
    -&gt;entityCondition('bundle', 'referee')
    -&gt;fieldCondition('field_referee_id‎', 'value', '1', '=');
    $result = $query-&gt;execute();
?&gt;


Further information: If I remove the field condition line from the above code it works perfectly. So the problems seems to be around finding the field_referee_id.

Code references and examples

EntityFieldQuery condition

https://www.drupal.org/node/1343708

Alternative answer: 
If you don't know what is causing the above problem I will accept alternative methods of achieving the same outcome as the correct answer.
The code above seems right only problem here might be the machine name of the field is not same as the one given in 
->fieldCondition('field_referee_id‎', 'value', '1', '=');
or the field might be multivalued field, for multivalued field in place of '=' 'IN' should be used.