The private internet company hired by former secretary of state Hillary Clinton to maintain her private email server has been obstructing a congressional investigation into its actions for more than a year, prompting a leading lawmakers to refer the case to the Trump administration’s Department of Justice for criminal prosecution.

Rep. Lamar Smith (R., Texas), chairman of the House Science, Space, and Technology Committee, has asked the DOJ to prosecute Platte River Networks CEO Treve Suazo for obstructing a congressional investigation into his company’s role in providing security for Clinton’s home brewed email server, which became the subject of widespread debate following revelations that it had multiple security vulnerabilities.

Smith, whose committee has jurisdiction over the investigation, said the Congress would not tolerate Platte River's failure to comply with the investigation.

"The Committee is referring Mr. Treve Suazo, CEO of Platte River Networks, to the Department of Justice for prosecution under federal laws pertaining to failing to produce subpoenaed documents, making false statements to Congress regarding possession of documents, and obstructing Congress," Smith said in a statement.

"Platte River Networks, a company hired by former Secretary Hillary Clinton, has deliberately withheld requested materials from the Committee and refused to comply with lawfully issued subpoenas," Smith alleged. "With a new administration in place, I am hopeful that the Department of Justice will appropriately respond to the referral. We cannot allow companies with valuable information to stonewall us in our oversight efforts."

Senior congressional aides apprised of the situation said their investigation shows there is mounting evidence there were "pretty serious cyber security concerns" with Clinton’s server.

Multiple subpoenas and letters from the congressional investigation team went unanswered by Platte River, prompting Smith to refer the case to the DOJ for criminal prosecution. Congressional investigators allege that the company is guilty of failing to produce key documents, making false statements to Congress, and of obstructing the investigation into Clinton’s server.

Two other companies that were subpoenaed and investigated by the committee complied with requests for information. Only Platte River declined to help, according to committee staff.

At least two subpoenas issued by the committee were not answered by Platte River.

"This is atypical," said one committee aid who brief reporters on the situation. "There were absolutely zero negotiations, there was no willingness on their part to discuss whether any information they would provide would satisfy the committee's request. It was just the company, with council, refusing to discuss" the matter.

Clinton’s server had many security vulnerabilities and was subjected to multiple hack attacks, according to committee staff.

There were "serious concerns about the vulnerability of information stored on the server because that information was not encrypted," one aide disclosed.

Warning issued by other companies working on the server warned that inadequate encryption methods had been employed, according to the committee aides.

"Those security alerts detailed numerous attempts to hack Clinton’s server" from North Korea, Germany, the United States, and elsewhere, according to one committee aide.

Update 11:26 a.m.: This post has been updated with further information.

Update 1:16 p.m.: Department of Justice spokesman Ian Prior said the Department has received and is reviewing the letter but declines further comment.