diff --git a/src/main/java/com/sk89q/worldguard/bukkit/listener/RegionProtectionListener.java b/src/main/java/com/sk89q/worldguard/bukkit/listener/RegionProtectionListener.java
index e6eac706..036594fb 100644
--- a/src/main/java/com/sk89q/worldguard/bukkit/listener/RegionProtectionListener.java
+++ b/src/main/java/com/sk89q/worldguard/bukkit/listener/RegionProtectionListener.java
@@ -152,7 +152,9 @@ public void onPlaceBlock(final PlaceBlockEvent event) {
         final RegionAssociable associable = createRegionAssociable(event.getCause());
 
         // Don't check liquid flow unless it's enabled
-        if (Materials.isLiquid(type) && !getWorldConfig(event.getWorld()).checkLiquidFlow) {
+        if (event.getCause().getRootCause() instanceof Block
+                && Materials.isLiquid(type)
+                && !getWorldConfig(event.getWorld()).checkLiquidFlow) {
             return;
         }