diff --git a/src/mceditlib/anvil/adapter.py b/src/mceditlib/anvil/adapter.py
index 47c9594..6db2f05 100644
--- a/src/mceditlib/anvil/adapter.py
+++ b/src/mceditlib/anvil/adapter.py
@@ -212,10 +212,13 @@ class AnvilChunkData(object):
             levelTag["Biomes"] = nbt.TAG_Byte_Array(numpy.empty((16, 16), 'uint8'))
             levelTag["Biomes"].value[:] = -1
 
-        self.Entities = [PCEntityRef(tag) for tag in self.rootTag["Level"]["Entities"]]
-        del self.rootTag["Level"]["Entities"]
-        self.TileEntities = [PCTileEntityRef(tag) for tag in self.rootTag["Level"]["TileEntities"]]
-        del self.rootTag["Level"]["TileEntities"]
+        self.Entities = self.rootTag["Level"]["Entities"]
+        self.TileEntities = self.rootTag["Level"]["TileEntities"]
+
+        # self.Entities = [PCEntityRef(tag) for tag in self.rootTag["Level"]["Entities"]]
+        # del self.rootTag["Level"]["Entities"]
+        # self.TileEntities = [PCTileEntityRef(tag) for tag in self.rootTag["Level"]["TileEntities"]]
+        # del self.rootTag["Level"]["TileEntities"]
 
     def _create(self):
         chunkTag = nbt.TAG_Compound()
@@ -264,8 +267,6 @@ class AnvilChunkData(object):
             sections.append(section.buildNBTTag())
 
         tag["Level"]["Sections"] = sections
-        tag["Level"]["Entities"] = nbt.TAG_List([ref.rootTag for ref in self.Entities])
-        tag["Level"]["TileEntities"] = nbt.TAG_List([ref.rootTag for ref in self.TileEntities])
 
         log.debug(u"Saved chunk {0}".format(self))
         return tag
diff --git a/src/mceditlib/anvil/entities.py b/src/mceditlib/anvil/entities.py
index 594ab59..e42d17a 100644
--- a/src/mceditlib/anvil/entities.py
+++ b/src/mceditlib/anvil/entities.py
@@ -11,8 +11,9 @@ log = logging.getLogger(__name__)
 
 
 class PCEntityRef(object):
-    def __init__(self, rootTag):
+    def __init__(self, rootTag, chunk=None):
         self.rootTag = rootTag
+        self.chunk = chunk
 
     def raw_tag(self):
         return self.rootTag
@@ -32,12 +33,13 @@ class PCEntityRef(object):
         entity = newEntityClass(tag)
         entity.Position = self.Position + copyOffset
 
-        return PCEntityRef(tag)
+        return PCEntityRef(tag, None)
 
 
 class PCTileEntityRef(object):
-    def __init__(self, rootTag):
+    def __init__(self, rootTag, chunk=None):
         self.rootTag = rootTag
+        self.chunk = chunk
 
     def raw_tag(self):
         return self.rootTag
diff --git a/src/mceditlib/schematic.py b/src/mceditlib/schematic.py
index d9627fa..7757379 100644
--- a/src/mceditlib/schematic.py
+++ b/src/mceditlib/schematic.py
@@ -156,8 +156,8 @@ class SchematicFileAdapter(FakeChunkedLevelAdapter):
 
         self.rootTag["Data"].value &= 0xF  # discard high bits
 
-        self.Entities = [self.EntityRef(tag) for tag in self.rootTag["Entities"]]
-        self.TileEntities = [self.EntityRef(tag) for tag in self.rootTag["TileEntities"]]
+        self.Entities = [self.EntityRef(tag, None) for tag in self.rootTag["Entities"]]
+        self.TileEntities = [self.EntityRef(tag, None) for tag in self.rootTag["TileEntities"]]
 
 
     def saveChanges(self):
diff --git a/src/mceditlib/worldeditor.py b/src/mceditlib/worldeditor.py
index 3bb4e71..84ae9de 100644
--- a/src/mceditlib/worldeditor.py
+++ b/src/mceditlib/worldeditor.py
@@ -48,6 +48,8 @@ class WorldEditorChunk(object):
         self.cx, self.cz = chunkData.cx, chunkData.cz
         self.dimName = chunkData.dimName
         self.dimension = editor.getDimension(self.dimName)
+        self.Entities = [editor.adapter.EntityRef(tag, self) for tag in chunkData.Entities]
+        self.TileEntities = [editor.adapter.TileEntityRef(tag, self) for tag in chunkData.TileEntities]
 
     def buildNBTTag(self):
         return self.chunkData.buildNBTTag()
@@ -101,14 +103,6 @@ class WorldEditorChunk(object):
     def HeightMap(self):
         return self.chunkData.HeightMap
 
-    @property
-    def Entities(self):
-        return self.chunkData.Entities
-
-    @property
-    def TileEntities(self):
-        return self.chunkData.TileEntities
-
     @property
     def TerrainPopulated(self):
         return self.chunkData.TerrainPopulated
@@ -117,6 +111,28 @@ class WorldEditorChunk(object):
     def TerrainPopulated(self, val):
         self.chunkData.TerrainPopulated = val
 
+    def addEntity(self, ref):
+        if ref.chunk is self:
+            return
+        self.chunkData.Entities.append(ref.rootTag)
+        self.Entities.append(ref)
+        ref.chunk = self
+
+    def addTileEntity(self, ref):
+        if ref.chunk is self:
+            return
+        self.chunkData.TileEntities.append(ref.rootTag)
+        self.TileEntities.append(ref)
+        ref.chunk = self
+
+    def removeTileEntity(self, ref):
+        if ref.chunk is not self:
+            return
+        self.chunkData.TileEntities.remove(ref.rootTag)
+        self.TileEntities.remove(ref)
+        ref.chunk = None
+        ref.rootTag = None
+
 
 class WorldEditor(object):
     def __init__(self, filename=None, create=False, readonly=False, adapterClass=None, adapter=None, resume=None):
@@ -606,7 +622,7 @@ class WorldEditorDimension(object):
         x, y, z = ref.Position
         cx, cz = chunk_pos(x, z)
         chunk = self.getChunk(cx, cz, create=True)
-        chunk.Entities.append(ref.copy())
+        chunk.addEntity(ref.copy())
 
     def addTileEntity(self, ref):
         x, y, z = ref.Position
@@ -615,9 +631,9 @@ class WorldEditorDimension(object):
         existing = [old for old in chunk.TileEntities
                     if old.Position == (x, y, z)]
         for e in existing:
-            chunk.TileEntities.remove(e)
+            chunk.removeTileEntity(e)
 
-        chunk.TileEntities.append(ref.copy())
+        chunk.addTileEntity(ref.copy())
 
     # --- Import/Export ---