diff --git a/js/libtextsecure.js b/js/libtextsecure.js
index 83422167a5..51689d8255 100644
--- a/js/libtextsecure.js
+++ b/js/libtextsecure.js
@@ -39577,9 +39577,8 @@ MessageReceiver.prototype = {
 
             promises.push(textsecure.storage.groups.getNumbers(decrypted.group.id).then(function(existingGroup) {
                 if (existingGroup === undefined) {
-                    var members = decrypted.group.members;
                     if (decrypted.group.type != textsecure.protobuf.GroupContext.Type.UPDATE) {
-                        members = [source];
+                        decrypted.group.members = [source];
                         console.log("Got message for unknown group");
                     }
                     return textsecure.storage.groups.createNewGroup(decrypted.group.members, decrypted.group.id);
diff --git a/libtextsecure/message_receiver.js b/libtextsecure/message_receiver.js
index 55e65d1915..c9419c88f7 100644
--- a/libtextsecure/message_receiver.js
+++ b/libtextsecure/message_receiver.js
@@ -297,9 +297,8 @@ MessageReceiver.prototype = {
 
             promises.push(textsecure.storage.groups.getNumbers(decrypted.group.id).then(function(existingGroup) {
                 if (existingGroup === undefined) {
-                    var members = decrypted.group.members;
                     if (decrypted.group.type != textsecure.protobuf.GroupContext.Type.UPDATE) {
-                        members = [source];
+                        decrypted.group.members = [source];
                         console.log("Got message for unknown group");
                     }
                     return textsecure.storage.groups.createNewGroup(decrypted.group.members, decrypted.group.id);