"I will never communicate via private chat platform," the actor said in a statement on his verified Twitter account. "And I would never ask individual fans for money for any reason."

Downey said any message from him will always come through his verified social media accounts, on which he has millions of followers.

"I am constantly humbled by the incredible love, support and generosity of our little community, " Downey said. "Some want to take advantage of that, so let's have each other's back."