Pres­i­dent Don­ald Trump on Thurs­day fired his em­bat­tled Home­land Se­cu­ri­ty Sec­re­tary Kristi Noem, af­ter mount­ing crit­i­cism over her lead­er­ship of the de­part­ment, in­clud­ing the han­dling of the ad­min­is­tra­tion’s im­mi­gra­tion crack­down and dis­as­ter re­sponse.

Trump, who said he would nom­i­nate Ok­la­homa Re­pub­li­can Sen. Mark­wayne Mullin in her place, made the an­nounce­ment on so­cial me­dia af­ter Noem faced a two-day grilling on Capi­tol Hill this week from GOP mem­bers as well as De­moc­rats.

Noem’s de­par­ture marks a stun­ning turn­around for a close al­ly to the pres­i­dent who was tasked with steer­ing his cen­ter­piece pol­i­cy of mass de­por­ta­tions. But she ap­peared to in­creas­ing­ly be­come a li­a­bil­i­ty for Trump, with ques­tions aris­ing over her spend­ing at her de­part­ment and over her con­duct in the af­ter­math of the shoot­ing deaths of two pro­test­ers in Min­neapo­lis ear­li­er this year.