diff --git a/lapis.c b/lapis.c
index ed9ba26..77f6993 100644
--- a/lapis.c
+++ b/lapis.c
@@ -677,7 +677,10 @@ lapis_node_t *lapis_parse_expr(int64_t *nnodes, FILE *f) {
     *nnodes = num_nodes;
     return nodes;
 ERROR:
-    if ( tokens != NULL ) free( tokens );
+    if ( tokens != NULL ) {
+        for (size_t n=0; n < ntokens; n++) lapis_token_free(&tokens[n]);
+        free(tokens);
+    }
     if ( oper_priorities != NULL ) free( oper_priorities );
     if ( oper_arg_form != NULL ) free( oper_arg_form );
     if ( nodes != NULL ) free( nodes );