diff --git a/pcbnew/connectivity_algo.cpp b/pcbnew/connectivity_algo.cpp
index c00fd04470..acac2d55e2 100644
--- a/pcbnew/connectivity_algo.cpp
+++ b/pcbnew/connectivity_algo.cpp
@@ -1,7 +1,7 @@
 /*
  * This program source code file is part of KICAD, a free EDA CAD application.
  *
- * Copyright (C) 2016-2017 CERN
+ * Copyright (C) 2016-2018 CERN
  * @author Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
  *
  * This program is free software; you can redistribute it and/or
@@ -1070,15 +1070,50 @@ bool CN_ANCHOR::IsDangling() const
     if( !m_cluster )
         return true;
 
-    int validCount = 0;
+    // Calculate the item count connected to this anchor.
+    // m_cluster groups all items connected, but they are not necessary connected
+    // at this coordinate point (they are only candidates)
+    BOARD_CONNECTED_ITEM* item_ref = Parent();
+    LSET layers = item_ref->GetLayerSet() & LSET::AllCuMask();
 
-    for( auto item : *m_cluster )
+    // the number of items connected to item_ref at ths anchor point
+    int connected_items_count = 0;
+
+    // the minimal number of items connected to item_ref
+    // at this anchor point to decide the anchor is *not* dangling
+    int minimal_count = 1;
+
+    // a via can be removed if connected to only one other item.
+    // the minimal_count is therefore 2
+    if( item_ref->Type() == PCB_VIA_T )
+        minimal_count = 2;
+
+    for( CN_ITEM* item : *m_cluster )
     {
-        if( item->Valid() )
-            validCount++;
+        if( !item->Valid() )
+            continue;
+
+        BOARD_CONNECTED_ITEM* brd_item = item->Parent();
+
+        if( brd_item == item_ref )
+            continue;
+
+        // count only items on the same layer at this coordinate (especially for zones)
+        if( !( brd_item->GetLayerSet() & layers ).any() )
+            continue;
+
+        if( brd_item->Type() == PCB_ZONE_AREA_T )
+        {
+            ZONE_CONTAINER* zone = static_cast<ZONE_CONTAINER*>( brd_item );
+
+            if( zone->HitTestInsideZone( wxPoint( Pos() ) ) )
+                connected_items_count++;
+        }
+        else if( brd_item->HitTest( wxPoint( Pos() ) ) )
+            connected_items_count++;
     }
 
-    return validCount <= 1;
+    return connected_items_count < minimal_count;
 }
 
 void CN_CONNECTIVITY_ALGO::SetProgressReporter( PROGRESS_REPORTER* aReporter )
diff --git a/pcbnew/tracks_cleaner.cpp b/pcbnew/tracks_cleaner.cpp
index 583efefdd3..a291c15331 100644
--- a/pcbnew/tracks_cleaner.cpp
+++ b/pcbnew/tracks_cleaner.cpp
@@ -1,9 +1,9 @@
 /*
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
- * Copyright (C) 2004-2017 Jean-Pierre Charras, jp.charras at wanadoo.fr
+ * Copyright (C) 2004-2018 Jean-Pierre Charras, jp.charras at wanadoo.fr
  * Copyright (C) 2011 Wayne Stambaugh <stambaughw@verizon.net>
- * Copyright (C) 1992-2017 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 1992-2018 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -40,6 +40,9 @@
 #include <connectivity_data.h>
 #include <connectivity_algo.h>
 
+#include <tool/tool_manager.h>
+#include <tools/pcb_actions.h>
+
 // Helper class used to clean tracks and vias
 class TRACKS_CLEANER
 {
@@ -153,6 +156,9 @@ void PCB_EDIT_FRAME::Clean_Pcb()
     BOARD_COMMIT commit( this );
     TRACKS_CLEANER cleaner( GetBoard(), commit );
 
+    // Clear current selection list to avoid selection of deleted items
+    GetToolManager()->RunAction( PCB_ACTIONS::selectionClear, true );
+
     bool modified = cleaner.CleanupBoard( dlg.m_deleteShortCircuits, dlg.m_cleanVias,
                             dlg.m_mergeSegments, dlg.m_deleteUnconnectedSegm );
 
@@ -252,7 +258,6 @@ bool TRACKS_CLEANER::CleanupBoard( bool aRemoveMisConnected,
 TRACKS_CLEANER::TRACKS_CLEANER( BOARD* aPcb, BOARD_COMMIT& aCommit )
     : m_brd( aPcb ), m_commit( aCommit )
 {
-
 }