President Trump's son-in-law Jared Kushner and daughter Ivanka Trump re-routed their personal email accounts to computers run by the Trump Organization as public scrutiny intensified over their use of private emails to conduct White House business, internet registration records show.

The move, made just days after Kushner’s use of a personal email account first became public, came shortly after special counsel Robert Mueller asked the White House to turn over records related to his investigation of Russia's interference in the 2016 election and possible collusion with Trump associates. It also more closely intertwines President Trump’s administration with his constellation of private businesses.

Kushner, who is a senior adviser to the president, first faced scrutiny for his private email use on Sept. 24, when his lawyer confirmed that he had occasionally used a personal email account to communicate with other White House officials. Kushner's contacts with Russians during the presidential campaign have drawn the attention of federal investigators.

According to internet registration records reviewed by USA TODAY and cybersecurity researchers, Kushner and his wife Ivanka Trump, who is also a senior adviser, re-routed their email accounts to a server operated by the Trump Organization on either Sept. 26 or 27, as attention from the media and lawmakers intensified.

The Trump Organization did not respond to questions Tuesday about the email accounts.

A spokesman for Kushner and Ivanka Trump, who spoke only on condition of anonymity because they were not directly involved with the technical details, said in a statement that the couple's personal email "does not reside and never has resided in, nor passed through, through the Trump Organization email server." Instead, the spokesman said Kushner and Trump and used a "filtering service" to block viruses and malware.

Last week, the leaders of the Senate Intelligence Committee, which is conducting its own investigation of Russian election interference, told Kushner they were “concerned” that they had heard about the emails in news reports instead of from him. The committee had asked him to turn over copies of emails related to the investigation.

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The registration records work like street signs – they direct internet traffic to specific computers connected to the network. One set of those records, known as mail exchange records, tells other computers where to send emails addressed to a particular domain.

The internet domain Kushner used for his personal emails was first registered in December. In March, mail exchange records for Kushner and Trump’s family email domain, ijkfamily.com, directed messages to an email system run by Microsoft. The registration was updated at the end of September. Now it points to two mail servers used by the Trump Organization.

USA TODAY reviewed the registration records. Nicholas Weaver, a researcher at the International Computer Science Institute, also reviewed the records and reached the same conclusion. “All indications are these emails are handled by a Trump Organization server,” Weaver said.

The records do not specify whether the emails remain on the Trump Organization server, or simply pass through and are later delivered somewhere else.

Lawyers and cybersecurity researchers said the move was puzzling.

Renato Mariotti, a former federal prosecutor, said that while the emails Kushner and Trump sent and received through their personal accounts could well have been innocuous – locating them on computers run by the Trump Organization “certainly creates the appearance of potential impropriety.”

Mariotti said the move raises questions about who at the Trump-owned company might have access to emails regarding White House business.

The Trump Organization did not respond to questions Tuesday about whether anyone at the company had access to the messages.

Trump, who refused to fully divest from his businesses, resigned from his real estate and branding empire the day before he took office in January. He instead ceded control of the businesses to a revocable trust run for his benefit by two of his sons and a longtime Trump Organization employee. Ivanka Trump and Kushner also separated themselves from their own businesses before taking senior roles in the administration.

Kushner’s lawyer, Abbe Lowell, said in a statement last week that Kushner had taken steps to preserve work-related emails from his personal account by forwarding copies to his White House email account.