A photograph of Ted Cruz taken on an American Airlines flight on Sunday appears to show the Texas Senator without a face mask, seemingly in violation of the airline’s policy requiring that passengers wear face coverings to help avoid potential spread of the coronavirus.

American Airlines customers are required to wear face coverings while on board flights, a policy that is enforced at the airline’s gates in airports to make sure passengers enter the plane while wearing face masks. The policy does not apply to those eating or drinking, though the airline has asked people to cover their faces as soon as they’re done.

While Cruz appears to be holding a beverage in the photo, it’s not clear whether he has moved a face covering from his mouth before drinking — a mask isn’t visible at all in the picture. Another image of Cruz outside the flight’s gate also shows him without a mask.

Responding to a request for comment from TIME, a representative for Cruz pointed to an additional photo of him wearing a mask on the flight, however, and said he had removed it to drink.

“To help promote safety, Senator Cruz wears a mask when traveling, and practices social distancing where possible. Consistent with airline policy, he temporarily removes the mask while eating or drinking,” the spokesperson said in a statement. “Yesterday during his flight he removed his mask to drink and put it back on afterward. We should all practice common sense measures to slow the spread of the virus.”

Hosseh Enad, the Twitter user who shared the photos of Cruz without a face covering, did not immediately respond to a request for comment.

According to American Airlines, Cruz flew on one of the airline’s domestic regional partners.

“We are committed to protecting the health and safety of all those who fly with us, and we are reviewing the details of this matter,” the airline said in a statement.

The airline has previously received attention over its enforcement of the face coverings policy. In June, the conservative activist Brandon Straka was removed from an American Airlines flight because he refused to wear a mask. American Airlines then banned Straka from all of its flights as long as requirements for face coverings are in place.

Write to Mahita Gajanan at mahita.gajanan@time.com.