Sen. Thom Tillis (R-NC) issued a statement on Friday expressing regret for not taking adequate precautions against COVID-19 after he was caught on camera not wearing a mask in the tightly packed crowd of nearly 2,000 people during President Donald Trump’s RNC speech the night before.

“I’ve stressed the importance of mask wearing throughout this pandemic and have tried to lead by example on this issue, but last night I fell short of my own standard,” Tillis, who faces a tough re-election bid this fall, said before using the opportunity to attack his Democratic opponent Cal Cunningham.

Earlier in the evening, Tillis posted a photo of himself wearing a mask on the South Lawn along with the message, “I am honored to be in Washington for President @realDonaldTrump’s acceptance speech for the @GOP nomination, where he will share with America our continued vision of freedom, prosperity, and opportunity to live the American Dream.”

In response, Cunningham tweeted, “Sen. Thom Tillis criticized folks for not wearing masks, until Washington Republicans were the culprits. His attendance last night shows North Carolinians that the rules don’t apply to his colleagues in Washington—and that his talk about fighting this pandemic is just that: talk.”