diff --git a/client/mapHandler.cpp b/client/mapHandler.cpp
index aa3012ab3..e08938d31 100644
--- a/client/mapHandler.cpp
+++ b/client/mapHandler.cpp
@@ -1036,10 +1036,14 @@ IImage * CMapHandler::CMapBlitter::findBoatFlagBitmap(const CGBoat * boat, int a
 
 IImage * CMapHandler::CMapBlitter::findFlagBitmapInternal(std::shared_ptr<CAnimation> animation, int anim, int group, ui8 dir, bool moving) const
 {
+	size_t groupSize = animation->size(group);
+	if(groupSize == 0)
+		return nullptr;
+
 	if(moving)
-		return animation->getImage(anim % animation->size(group), group);
+		return animation->getImage(anim % groupSize, group);
 	else
-		return animation->getImage((anim / 4) % animation->size(group), group);
+		return animation->getImage((anim / 4) % groupSize, group);
 }
 
 CMapHandler::AnimBitmapHolder CMapHandler::CMapBlitter::findObjectBitmap(const CGObjectInstance * obj, int anim) const
@@ -1053,7 +1057,13 @@ CMapHandler::AnimBitmapHolder CMapHandler::CMapBlitter::findObjectBitmap(const C
 
 	// normal object
 	std::shared_ptr<CAnimation> animation = graphics->getAnimation(obj);
-	IImage * bitmap = animation->getImage((anim + getPhaseShift(obj)) % animation->size());
+	size_t groupSize = animation->size();
+    if(groupSize == 0)
+		return CMapHandler::AnimBitmapHolder();
+
+	IImage * bitmap = animation->getImage((anim + getPhaseShift(obj)) % groupSize);
+	if(!bitmap)
+		return CMapHandler::AnimBitmapHolder();
 
 	bitmap->setFlagColor(obj->tempOwner);