diff --git a/mammoth/docx/body_xml.py b/mammoth/docx/body_xml.py
index 2a1ffaf..2f7a38f 100644
--- a/mammoth/docx/body_xml.py
+++ b/mammoth/docx/body_xml.py
@@ -487,7 +487,7 @@ def create(**kwargs):
                 **kwargs
             ))
 
-        if relationship_id is not None:
+        if relationship_id is not None and relationships.find_target_by_relationship_id(relationship_id) is not None:
             href = relationships.find_target_by_relationship_id(relationship_id)
             if anchor is not None:
                 href = replace_fragment(href, anchor)
@@ -578,9 +578,9 @@ def _read_image(image_file, alt_text):
     def _find_blip_image(element):
         embed_relationship_id = element.attributes.get("r:embed")
         link_relationship_id = element.attributes.get("r:link")
-        if embed_relationship_id is not None:
+        if embed_relationship_id is not None and relationships.find_target_by_relationship_id(embed_relationship_id) is not None:
             return _find_embedded_image(embed_relationship_id)
-        elif link_relationship_id is not None:
+        elif link_relationship_id is not None and relationships.find_target_by_relationship_id(link_relationship_id) is not None:
             return _find_linked_image(link_relationship_id)
         else:
             return None
@@ -609,7 +609,7 @@ def open_image():
 
     def read_imagedata(element):
         relationship_id = element.attributes.get("r:id")
-        if relationship_id is None:
+        if relationship_id is None or relationships.find_target_by_relationship_id(relationship_id) is None:
             warning = results.warning("A v:imagedata element without a relationship ID was ignored")
             return _empty_result_with_message(warning)
         else:
diff --git a/mammoth/docx/relationships_xml.py b/mammoth/docx/relationships_xml.py
index 555ba2d..8bdbb8b 100644
--- a/mammoth/docx/relationships_xml.py
+++ b/mammoth/docx/relationships_xml.py
@@ -12,10 +12,10 @@ def __init__(self, relationships):
             self._targets_by_type[relationship.type].append(relationship.target)
     
     def find_target_by_relationship_id(self, key):
-        return self._targets_by_id[key]
+        return self._targets_by_id.get(key, None)
     
     def find_targets_by_type(self, relationship_type):
-        return self._targets_by_type[relationship_type]
+        return self._targets_by_type.get(relationship_type, [])
 
 
 Relationships.EMPTY = Relationships([])
@@ -26,7 +26,7 @@ def find_targets_by_type(self, relationship_type):
 
 def read_relationships_xml_element(element):
     children = element.find_children("relationships:Relationship")
-    return Relationships(list(map(_read_relationship, children)))
+    return Relationships(list(filter(lambda x: x.target not in ('../NULL', 'NULL', 'word/../NULL'), map(_read_relationship, children))))
 
 
 def _read_relationship(element):