Security Update 2016-002 could not be verified

I am running Yosemite 10.10.5. Was prompted this afternoon to install system update "Security Update 2016-002". It did a 461 MB download and then forced a restart. After restart, the update proceeded for a few seconds and then unexpectedly terminated with a pop up that said the downloaded update could not be verified. Here's the error prompt: "Security Update 2016-002 could not be verified. It may have been corrupted or tampered with during downloading. Click Update to download and check the update again". I did this three times. The update failed each time, same reason in the error message. Did this update go through QA? Any thoughts on this?