10:07 AM PT -- Walter Jones, who played the black ranger in 'MMPR,' tells TMZ ... "He was an inspiration to so many people. His presence will be dearly missed. It’s so sad to lose another member of our Ranger family."
He adds, "Jason was one of the biggest pranksters on the show. He had a wild sense of humor. We had our shares of ups and downs but I stayed consistent about being an ear if he needed one. My prayers go out to his family and all that will miss him."
Jason David Frank -- one of the original "Power Rangers" -- has died ... TMZ has learned.
The actor and mixed martial artist died in Texas, according to his rep Justine Hunt. Sources with direct knowledge tell us his death was the result of suicide.
JDF is best known as Tommy Oliver from the original run of the "Mighty Morphin Power Rangers" franchise, dating back to the kids series' debut in 1993 ... when he was introduced as one of six crime/monster-fighting superheroes, masked head to toe with kung-fu skills.
Fans will remember ... he started out as the Green Ranger in Season 1, introduced at first as an enemy of the Power Rangers -- only to do a 180 and become good. After his powers start to deteriorate, however, he's turned into the White Ranger ... and tapped as the new leader of the group. Frank starred as one of the leads for 3 seasons, totaling 123 episodes.
Frank went on to reprise his role as Tommy in several adaptions of 'Power Rangers' -- including 'Wild Force,' 'Turbo,' 'Zeo,' 'Dino Thunder,' 'Megaforce,' 'Ninja Steel,' 'HyperForce,' and more. He's been a Red Ranger, a Black Ranger and a Green Ranger anew. JDF is a fan favorite Power Ranger ... which is why he's returned to the franchise time and again.
His onscreen fighting abilities translated into the real world ... Frank was a professionally trained MMA brawler, who was well-versed in everything from Taekwondo, Muay Thai, Judo, Brazilian Jiu-Jitsu and others. He fought professionally for a time from 2008 to 2010.
He's survived by his four children.
Jason's rep Justinetells TMZ ... "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. He loved his family, friends and fans very much. He will truly be missed."
Frank was 49.
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