A witness has been subpoenaed to appear before a grand jury in the case of California Rep. Duncan Hunter in relation to questionable use of campaign cash.

The San Diego Union-Tribune reported that a subpoena dated Dec. 21 by the U.S. District Court in San Diego was sent to a business and commanded the witness to appear before the jury in San Diego.

Hunter reportedly spent thousands of dollars at the business, which was not identified in the report, according to Federal Election Commission documents that were provided to the newspaper.

The subpoena orders the recipient to “provide any and all documents, to include itemized and signed receipts, event contracts, reservation/booking details, name(s) of guest(s) … guest folios, photographs, social media postings and any form of communication associated with” six transactions in 2012.

Hunter is currently under federal criminal investigation for the use of campaign money for personal use. He has since reimbursed his campaign for many of the expenses.

Hunter’s attorneys did not respond for comment. In a radio interview on Tuesday, Hunter expressed dismay at how the Department of Justice was handling both his investigation and investigations relating to President Donald Trump.

“I think it’s just like everything, you have people who are partisan, people that want to get famous, people that want to prosecute as opposed to finding justice, and that’s what you have,” he said. “And those are the types of people, unfortunately, that rise to the top levels of these organizations like the FBI and the Department of Justice.”

Hunter’s legal fees have also been a problem for him. During the third fundraising quarter, he spent more money on them than he raised.

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