(Reuters) -Two officials at the U.S. Department of Justice's antitrust division have been fired for insubordination, a source familiar with the decision said on Tuesday, as controversy builds over how the DOJ reached a recent settlement greenlighting Hewlett Packard Enterprise's $14 billion acquisition of Juniper Networks.

The source said the firings removed two top deputies of Assistant Attorney General Gail Slater, a former JD Vance advisor who leads the antitrust division. The move exposed a power struggle within President Donald Trump's administration between proponents of robust antitrust enforcement and dealmakers seeking to leverage influence.

Roger Alford, a former official during the first Trump administration who was Slater's top deputy, and Bill Rinner, a former counsel at hedge fund Apollo Global Management who was in charge of merger enforcement, were no longer listed among antitrust leadership on a Justice Department website on Tuesday.

Alford and Rinner did not immediately respond to requests for comment.

Shortly after Trump took office in January, the Justice Department sued to block the deal, alleging it would harm competition in the market for wireless networking solutions used by large enterprises. HP Enterprise started negotiating the deal with the DOJ on March 25, around two weeks after Slater was sworn in, according to court papers.

Ahead of a scheduled trial, the DOJ agreed to drop its claims in exchange for HP Enterprise agreeing to license some of Juniper's AI technology to competitors and sell off a unit that caters to small and mid-sized businesses. 

Slater and several Justice officials, including Rinner and Alford, signed the settlement rather than staff attorneys on the case, a move that sources familiar with merger protocol called unusual.

Chad Mizelle, Attorney General Pam Bondi's chief of staff, was one of the officials who signed the deal. 

Mizelle had directed the antitrust division to settle the case, according to a person briefed on the matter. After Slater pushed back, Mizelle sought to fire Slater's deputies in retaliation, the person said.

Four Democratic senators led by Elizabeth Warren of Massachusetts, on Tuesday called on the federal judge overseeing the merger case to hold a hearing on whether the settlement is in the public interest.

U.S. law seeks to guard against backdoor merger clearance of merger deals by requiring merging companies to disclose communications with "any officer or employee of the United States concerning or relevant to" a settlement proposal.

The senators want U.S. District Judge Casey Pitts in San Jose, California, to probe whether companies hired consultants to lobby the White House in support of the deal and failed to disclose them.

"If this or any other transaction is approved based on political favors rather than on the merits, the public will surely bear the cost," the senators wrote.

HP Enterprise spokesperson Adam Bauer said the company is "confident our acquisition of Juniper Networks is in the public interest and will promote further competition in the enterprise WLAN market," adding "the transaction was appropriately approved with certain remedies by the U.S. Department of Justice, and it was unconditionally approved by 13 other antitrust regulators around the world."