President Trump's Homeland Security adviser Thomas Bossert resigns

(AP) -- President Donald Trump's homeland security adviser Thomas Bossert resigned Tuesday in the latest White House shakeup.

White House Press Secretary Sarah Huckabee Sanders said in a statement that Trump was "grateful for Tom's commitment to the safety and security of our great country."

Bossert was the point person in the White House on protecting the nation from terror and cyber threats. He also helped spearhead the administration's response to last year's hurricanes in Texas, Florida and Puerto Rico.

His exit comes a day after new national security adviser John Bolton began his tenure. Bolton, a seasoned bureaucratic operator, had been expected to put his stamp on the National Security Council staff.

Bossert is the latest in a wave of both voluntary and forced departures from the West Wing in recent months that have sent morale in the White House to new lows.

Trump's administration has set new records for turnover in his 15 months in office at all levels, with Bossert marking at least the 13th official who held the rank of assistant to the president at the start of the administration to depart.