Latest security flap again focuses scrutiny on Waltz after he earlier added journalist to Yemen war-planning chat

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Michael Waltz, the embattled national security adviser to Donald Trump, and other members of the national security council have reportedly used personal Gmail accounts to conduct government business.

The apparent use of Gmail, a relatively insecure method of communication for high-level government officials, places further scrutiny upon Waltz, who is already under pressure after adding a journalist to a group chat on the commercial Signal app, where top US officials then planned and celebrated a US airstrike in Yemen last month.