After causing widespread shock in August when reports surfaced that he had gone to rehab for cocaine addiction, Zac Efron has finally broken his silence.

The actor uploaded an Instagram photo on Sept. 27 showing him crouched on rock with the landscape of Peru behind him. He captioned the shot, "Hey guys! Just returned from an incredible trip to Peru with my dad and wanted to thank you all for your support these past few weeks...means the world to me. Love you guys!"

The actor has also told the media that he's back to work and focusing on that for a while, according to The Belfast Telegraph. He stars alongside Billy Bob Thornton and Tom Welling in the drama Parkland, out in theaters Friday. He also uploaded a still from the film on Sept. 30.

"I'm doing what I set out to do," Efron said about his current focus on his career. "You have to go for it. You have to try. I want to challenge myself with tough parts. I wouldn't want it any other way. As an actor, my goal has always been to continue to challenge myself and learn and grow as an artist. I've been very lucky to have the chance to work alongside of great actors and directors. I couldn't ask for anything better."

Zac Efron News: Star Finished Rehab Stint Amid a Reported Cocaine Addiction?

Others in the industry have praised Efron for his decision to seek help, according to entertainmentwise.com.

"I'm not hip about [Efron's exact situation], but I think anybody who says, 'Hey, maybe I should go work on this,' more power to him," Tom Hanks said while out promoting his new film, Captain Phillips.

"Him seeking help encourages other people with addictive issues to seek help. It's brave of him," Marcia Gay Harden, who stars alongside Efron in Parkland, said.

Parkland follows the aftermath of President John F. Kennedy's assasination. He was taken to Parkland Memorial Hospital in Dallas after he was shot and later died there. Efron portrays Dr. Jim Carrico. The actor admitted he didn't have much knowledge about the historic shooting until he started filming, and was amazed by what he learned as a result.

"He's a young resident who suddenly has the most important man in the world thrust in front of him with fatal injuries," he said of his character. "He's called to action in a big way. You can't ask for more to do as an actor."

"I didn't know all that much about the details. The film is eye-opening. This was in a time before Twitter and cell phones. People watched this unfold for days on TV," he said.

Watch the trailer for Parkland below.

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