BANGKOK, Feb. 8 -- Thai action hero Tony Jaa is privately recovering after battling gallbladder cancer, according to a report by The Straits Times.

The 50-year-old martial arts icon - beloved for his gravity-defying stunts and raw, bone-crunching fight scenes - is said to be on the mend following surgery and ongoing chemotherapy.

Fans first grew concerned when Jaa posted a photo of himself on January 31 looking noticeably thinner.

"The journey is about to begin. One More Round," he wrote, referencing the title of a newly launched music video teaser - but offering no explanation for his physical transformation.

Thai outlet Nine Entertain, cited by The Straits Times, reported that a source close to Jaa revealed he was diagnosed with sta...