(AP/NBC) – U.S. Transportation Secretary Elaine Chao is resigning effective Monday, becoming the highest-ranking member of President Donald Trump’s administration to resign in protest after the pro-Trump insurrection at Capitol.

In a statement Thursday, Chao, who is married to Senate GOP leader Mitch McConnell, said the violent attack on the Capitol “has deeply troubled me in a way that I simply cannot set aside.”

She said her department will continue to cooperate with President-elect Joe Biden’s designated nominee to head the department, former South Bend, Indiana, Mayor Pete Buttigieg.

Her departure came after several other resignations by Trump administration officials on the heels of the riot.