After Donald Trump tweeted Monday that Immigration and Customs Enforcement (ICE) was set to begin rounding up illegal immigrants who were given deportation orders but had defied them and stayed in the country, The Washington Post ran a piece Friday that unveiled many of the details of the plan, apparently to the chagrin of the White House. That leak is now thought to have come from acting Homeland Security Secretary Kevin McAleenan, who had vocally disapproved of the plan and sought to “sabotage” it, according to the Washington Examiner.

In a move he said was to placate Democrats, President Trump announced on Saturday that the nationwide immigration enforcement operation planned to start Sunday — aimed at migrant families who illegally remain in the country despite being denied asylum — was called off to give lawmakers two weeks to work on a plan to fix legal “loopholes” he said have enticed migrants to come to the U.S.

However, all five officials who spoke with the Washington Examiner confirmed McAleenan’s decision to go rogue and stymie the operation was what prompted the White House to call off the 10-city operation.

I wrote about the media reaction to Trump’s Monday tweet, which was almost unanimous in its condemnation of the plan as one that was going to be logistically difficult to carry out. However, most of the early news reports were thin on the details.  By Friday, The Post seemed to have all the details of how the raid would work and mentioned McAleenan as an official who had reservations about the plan.

The “family op,” as it is referred to at ICE and the Department of Homeland Security, is slated to target up to 2,000 families in as many as 10 U.S. cities, including Houston, Chicago, Miami, Los Angeles and other major immigration destinations, said the officials, who spoke on the condition of anonymity to describe the law enforcement operation.

McAleenan has warned that an indiscriminate operation to arrest migrants in their homes and at work sites risks separating children from their parents in cases where the children are at day care, summer camp or friend’s houses. He also has maintained that ICE should not devote major resources to carrying out a mass interior sweep while telling lawmakers it needs emergency funding to address the crisis at the U.S. border.

The Examiner interviewed several current and former Trump administration officials and they all agree that McAleenan had  been fighting ICE Director Mark Morgan and other administration officials within and without the White House to scale back the operation. They believe the details in the Post report couldn’t have come from anyone else.

“I know he has not approved of this operation for months,” one person familiar with those private conversations said during a phone call Saturday night. “The president wouldn’t leak that. ICE wouldn’t leak that. There’s only a few people involved in these discussions … The only one who could have shared the details of those operations were Kevin.”

“That’s our belief,” a second official said when asked if McAleenan was behind the leak. “The secretary was not supportive from day one.”

The first official said McAleenan may have leaked it so that he could “be the martyr” in the face of anticipated blowback in the future.

A third official claimed McAleenan “cares more about what liberals and ‘Never Trumpers’ in Congress and the media think of him the achieving the express mission of his department.”

Trump ultimately called off Sunday’s raid with many outlets reporting that decision was primarily an attempt to give Democrats a chance to work with Republicans in Congress to reach a legislative solution to the immigration crisis.

However, it would appear the raid was also in jeopardy because one high-ranking official in the administration itself chose to use the media to fight his battle when he couldn’t convince his colleagues to listen to him.