The actor and MMA fighter was 49.
"Unfortunately, it is true," the rep told the publication. "Please respect the privacy of his family and friends during this horrible time as we come to terms with the loss of such a wonderful human being."
The statement added, "He loved his family, friends and fans very much. He will be truly missed."
So far, no cause of death has been revealed.
On Sunday, Frank was remembered by co-star Walter E. Jones, who played Zack Taylor, the black ranger.
"Can’t believe it…. RIP Jason David Frank🙏🏾," Jones wrote. "My heart is sad to have lost another member of our special family. #jasondavidfrank #jdf #walterejones #greenranger #whiteranger #mmpr #maythepowerprotectyou #tommy."
Fellow Power Ranger Alan Palmer shared a statement with ET on his co-star's passing. "Jason had a positive impact on everyone he came in contact with. I wish he could have felt the love that others had for him while he was still here. To the entire family of Power Ranger cast and fans , if you are feeling lonely, hopeless or down, please reach out to someone. You matter to more than you might think," he shared.
Amy Jo Johnson, who played Kimberly, the pink ranger, honored Frank in an Instagram post.
"Jase, you were beautiful and truly unique," she wrote. "My life just won’t be the same without your frenetic, hilarious, caring, driven and creative ball of energy. I will always love you, dear friend. Please Rest now In Peace…"
On Sunday evening, David Yost paid tribute to his co-star as well, writing, "My complicated friend You had my heart on day one So intelligent, so funny, so energetic A light so bright, a force like no other."
Frank rose to fame as Tommy Oliver. The then-teen made his debut on the series in 1993 as villain turned green ranger. Throughout the series, which ran until 1996, Frank would go on to become white power ranger and red zeo-ranger.
In addition to the television show, the actor reprised his role in the Mighty Morphin Power Rangers Movie, Power Rangers Turbo, Zeo and Dino Thunder.
Frank’s other acting credits also include, Sweet Valley High, Family Matters and We Bare Bears. According to his IMBD, prior to his death, Frank was working on a film called The Legend of the White Dragon.
Outside of acting, Frank was a professionally trained MMA fighter who studied Taekwondo, Muay Thai, Judo and Brazilian Jiu-Jitsu.
Frank is survived by his four children, Jenna, Skye, Jacob and Hunter.