This DHS Icon is a Google function that is part of their advanced security alert system. It has been designed to act as a warning to inform you that something may not be correct on your account, or that there has been a suspicious activity.
Here is some further information on this DHS icon and what it means.
It could be a warning that you're signed in on a different device or location, or there is an unknown security issue that Google wants to investigate further.
If you haven't logged in from a particularly unsecure location, then the DHS icon is warning you that the account you're using is potentially unsafe.
You'll need to ensure that you have the most secure and updated version of your password for the account.
It could also be a message from Google that your account could be at risk of phishing or hacking.
If you click on the DHS icon you'll be taken to a page with detailed information about the alert and ways to ensure your safety.
If you have further questions on this, here is a helpful link from Google Security which you can check out: https://support.google.com/accounts/answer/3466521?co=GENIE.Platform%3DAndroid&hl=en
