Millionaire Robert Durst appeared in court Tuesday and plead not guilty to a federal gun charge.

NBC News noted that the 72-year-old real estate heir was brought into court for a hearing that only lasted about 10 minutes. After entering his plea, he was taken back to the mental health facility of the jail where he is being held.

Durst, who is the son of real estate mogul Seymour Durst and the brother of commercial developer Douglas Durst, was arrested last month in New Orleans on a murder warrant signed by a Los Angeles judge.

The federal charge of possessing a firearm is the latest charge against him.

The Associated Press noted that Judge Lance Africk scheduled his trial date for June 22.

Durst will face the murder charge once he is extradited back to California. He is believed to have murdered his friend, Susan Berman, in Beverly Hills in 2000.

Suspicions swirled around him for years, but what many believe was a bombshell confession happened during the final moments of the HBO documentary The Jinx. A microphone picked up Durst saying what sounded like "What the hell did I do? Killed them all, of course."

Durst is estranged from his family who operates 1 World Trade Center as well as several other buildings that are part of the New York City skyline.