Actor Jared Padalecki says he will “never forget” the support he received from thousands of fans who lit candles at a Comic-Con event to honour his public campaign to fight mental illness.

Participating on a TV panel with his “Supernatural” co-stars at Comic-Con in San Diego over the weekend, Padalecki was before an audience of thousands when he looked out and saw lights dotting the crowd.

Turns out, fans had arranged to hold tea candles to show their support for the actor, who has recently gone public with his own battle with depression. However, the actor knew nothing of it beforehand.

Earlier this year, Padalecki revealed his own past struggles with mental illness, and launched the Always Keep Fighting campaign to help people fighting depression, self-injury, addiction and suicide.

In a Facebook post, Padalecki said he initially mistook the glow from the candles for cell phone cameras.

“Then, when I had a light given to me with an explanation of what it was and what it stood for, I was (and am still) gob-smacked,” Padalecki wrote.

The actor, who is also known for his role on the hit series “Gilmore Girls,” thanked the fans “from the very bottom of my heart,” and said it was a moment he will never forget.

“To everybody who held a light for me, please know that I hold my light for you.”

Padalecki later told a news outlet that it “took everything in my power not to cry” when he realized that audience members were holding up lights to honour his campaign.

On Twitter, William Shatner also showed his support, tweeting at Padalecki his regrets for not being in the audience: