A federal judge has ordered dozens of bankruptcy professionals to file sworn statements concerning their conversations with Bloomberg LP reporters involving troubled rare-earths mining company Molycorp Inc.

The order, signed last week by Judge Christopher Sontchi of the U.S. Bankruptcy Court in Wilmington, Del., cites concerns that information leaked from mediation may have been used in Bloomberg articles in recent months.

Backed by the Reporters Committee for Freedom of the Press and other news organizations, Bloomberg asked the judge to reconsider his order, warning it threatens to chill journalists' ability to report on the contentious proceeding.

Bloomberg has been reporting on the fight between bondholders and buyout firm Oaktree Capital Management L.P., Molycorp's senior lender, over the company's chapter 11 restructuring.

On Tuesday, Judge Sontchi refused to speed up the schedule for arguments over the order. He also refused to hold up his order for 48 hours to give Bloomberg an opportunity to go to federal court for an emergency order to upset his ruling.

After being turned down in bankruptcy court, Bloomberg's lawyers went to the U.S. District Court in Wilmington, Del., seeking an emergency hearing and stay.

Judge Sontchi's order "implicates serious First Amendment concerns," lawyers for the news organization wrote in federal court papers.

The order requires people working on Molycorp's case to detail their contacts with Bloomberg reporters. It requires the filing of "a sworn declaration regarding communications about Molycorp that they may have had, or known about others having, with reporters from Bloomberg in the last 60 days."

Bloomberg's lawyers say the order "sweeps in, and requires a report to the government regarding, two months worth of newsgathering by Bloomberg that is not alleged to involve any violation of a court order or any law or rule." The news organization's lawyers attacked it as vague and overbroad.

The judge's decision to gather evidence of talks with reporters adds another layer of complication to a bankruptcy proceeding that has been marked by bitter exchanges between senior and junior creditors and a high level of secrecy.

At a recent court hearing, Gregory Horowitz, a lawyer for the bondholders, told Judge Sontchi the professionals require "real meaningful adult supervision" to make progress toward a favorable outcome. Oaktree has said it came to Molycorp's aid when the company was in distress.

Molycorp filed for chapter 11 protection last year, its business plan upended by a change in Chinese trade policy that sent prices for its products plunging. Oaktree and bondholders clashed over financing, auction plans and prospects of litigation involving debt that piled as Molycorp ran into trouble.

Meanwhile, bondholders have complained that key information about the company's future was kept out of sight, including for a time, the financial data Molycorp is required to disclose to creditors being asked to vote on the plan. Those numbers were eventually revealed, setting off howls of protest from bondholders that the revelation was designed to put a damper on a bankruptcy auction.

Still under seal are large swaths of a lawsuit Molycorp's creditors have filed against Oaktree. In court hearings, lawyers for junior creditors have said creditors' chances of recovery hang largely on the strength of the legal claims in the suit, which are largely out of view.

Write to Peg Brickley at peg.brickley@wsj.com

(END) Dow Jones Newswires

January 19, 2016 18:45 ET (23:45 GMT)

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