Ackles shared the news at a 'Supernatural' fan convention when Padalecki was unable to attend the event.
While speaking at Creation Entertainment’s Supernatural Official Conventions -- a fan event held in East Brunswick, New Jersey, on Sunday -- Ackles explained why he was at the event without his on-screen brother and fellow demon hunter.
"I miss my buddy... [he] sends his love. I spoke with him yesterday. He’s sad he can’t be here," Ackles, 44, shared.
According to videos shared by fans, Ackles explained that he'd spoken with Padalecki, and was given the OK to share some details about why he wasn't at the event.
"He was in a very bad car accident," Ackles said of the Walker star. "He wasn’t driving. He was in the passenger seat, and he’s lucky to be alive.”
On April 21, Padalecki shared an apology with fans on Twitter, and explained he would have to miss the event, although he did not elaborate as to why.
“He’s at home recovering, which -- the fact that he’s not even in the hospital right now is, like, blowing my mind because I saw the car,” Ackles said on Sunday, adding that Padalecki told him that the impact from the airbag made it feel like he "went 12 rounds with Tyson."
"But he is doing OK, and he’s moving around," Ackles shared. "But yeah, [it was a] really, really bad car accident. Just keep him in your thoughts, send him some love if you get a chance on social and he’ll be back with us soon.”
Neither Padalecki or Ackles have yet addressed the accident on social media, and it's unclear when or where the accident took place.