Sen. Rand Paul (R-Ky.) on Saturday celebrated Festivus with a series of tweets airing his grievances against various political figures.

The fake holiday, which was the focus of a "Seinfeld" episode, involves airing grievances against those who have been disappointments through the year.

"Good morning, #Festivus celebrants and twitter! Today, I will have an #AiringofGrievances to wish you a #HappyFestivus," Paul tweeted Saturday morning.

He went on to target several people, including President Trump.

He also had a grievance with former Sen. Harry Reid (D-Nev.), questioning how the Nevada Democrat never told him "about the aliens."

The grievance appeared to be a reference to a report earlier this month that the Pentagon acknowledged for the first time the existence of a program charged with investigating unidentified flying objects.

According to a New York Times report, the $22 million Advanced Aerospace Threat Identification Program began in 2007 and was funded primarily at the request of Reid, who has long had an interest in the topic.

He also aired a grievance with Sen. Orrin Hatch (R-Utah), who joked the previous day that he and his wife were not the 80-something couple arrested for transporting marijuana as gifts for family in Nebraska.

Paul has celebrated Festivus in the past.

He issued a series of tweets airing his grievances last year to celebrate the made-up holiday.