WASHINGTON (AP) " Senate Minority Leader Chuck Schumer called Wednesday for the firing of a top federal official and two House committees planned hearings as Democrats pivoted from a divisive fight over a border bill to what they called the Trump administration's "callous" treatment and "willful neglect" of thousands of detained migrants.

Democratic outrage was fueled by lawmakers who reported overcrowded, unsanitary conditions at South Texas detention facilities they visited this week, observations that a report by the Homeland Security Department's inspector general seemed to confirm. In addition, a Facebook group for Border Patrol agents surfaced that included flippant posts about migrants perishing in U.S. custody and references to two female House Democrats as "hoes."

The focus on the plight of thousands held along the southern border as they await permission to enter the U.S. promises to unite Democrats far more than they were last week during a messy battle over a $4.6 billion bill aimed at improving conditions for seized migrants.

The legislation's approval split Democrats between those saying it lacked sufficient constraints on how the administration would use the money and others saying it was more important to quickly provide the funds. It ended up pitting liberals against moderates and Senate Democrats, who strongly supported the measure as the best achievable compromise, against House Democrats, who were badly split.

Congress sent the measure last week to Trump, who signed it Monday. Congress returns next week from a July 4 recess.