diff --git a/CHANGES.rst b/CHANGES.rst
index ecaaa189d..e1d5e876d 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,3 +1,11 @@
+Changes in synapse v0.16.1-r1 (2016-07-08)
+==========================================
+
+THIS IS A CRITICAL SECURITY UPDATE.
+
+This fixes a bug which allowed users' accounts to be accessed by unauthorised
+users.
+
 Changes in synapse v0.16.1 (2016-06-20)
 =======================================
 
diff --git a/synapse/__init__.py b/synapse/__init__.py
index 3cd79b124..2750ad3f7 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -16,4 +16,4 @@
 """ This is a reference implementation of a Matrix home server.
 """
 
-__version__ = "0.16.1"
+__version__ = "0.16.1-r1"