(CNN) A government watchdog group is looking into a trip that Treasury Secretary Steve Mnuchin made recently with his wife, Louise Linton, aboard a government plane. On the trip, Mnuchin attended a luncheon for a local chamber of commerce and took a tour of Fort Knox, where he was joined by Senate Majority Leader Mitch McConnell.

The trip made headlines earlier this week after Linton posted to Instagram about it and set off a social media storm when she fired back at one commenter who criticized her. Linton has since deleted the post and apologized.

Now the Citizens for Responsiblity and Ethics in Washington (CREW) is investigating whether the purpose of the trip was actually to view the total solar eclipse.

Did Steven Mnuchin & Louise Linton use a gov't plane to get a better view of the eclipse? We FOIA'd to find out. https://t.co/uvzWjq1RV7 pic.twitter.com/wFJCYlwcLZ — Citizens for Ethics (@CREWcrew) August 23, 2017

The ethics watchdog filed a freedom of information request for records concerning the trip.

"The requested records would shed light on the justification for Secretary Mnuchin's use of a government plane, rather than a commercial flight, for a trip that seems to have been planned around the solar eclipse and to enable the Secretary to secure a viewpoint in the path of the eclipse's totality," according to a statement.

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