diff --git a/util/ng_find_matches.cpp b/util/ng_find_matches.cpp
index 9cbc955a..c406ee95 100644
--- a/util/ng_find_matches.cpp
+++ b/util/ng_find_matches.cpp
@@ -301,7 +301,7 @@ struct GraphCache {
                 vertex_reports_by_level[d][v].insert(rs.begin(), rs.end());
             }
 
-            if (edit_distance == 0) {
+            if (edit_distance == 0 || hamming) {
                 // if edit distance is 0, no predecessors will have reports
                 continue;
             }