Robert Downey Jr has urged social media followers to be wary of online scam-artists masquerading as him in a bid to obtain money from unassuming fans.

The Hollywood star, 52, reached out via his approved Facebook page on Wednesday afternoon after being made aware of various fake accounts and money-making scams created in his name.

Affectionately referring to his fans as ‘Ducklings, Honey Bunnies, or otherwise’, he wrote: ‘It has come to my attention that one or more scam artists have taken to impersonating me online and asking some of you via private message or chat for ‘donations’ for various ’causes.’

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A word of warning: Robert Downey, Jr has urged social media followers to be wary of online scam-artists masquerading as him in a bid to obtain money from unassuming fans

‘Just wanted to let you all know that if you encounter someone on a chat platform claiming to be me, they are lying. I will never ever communicate via private chat platforms, and I would never ask individual fans for money for any reason.’

Robert, whose associated charities and causes include the ALS Association, the Entertainment Industry Foundation and the Make-A-Wish Foundation, added: ‘Any communication from me will originate from my public, verified social media pages, and all fundraising is done via broad, public campaigns.

‘I am constantly humbled by the incredible love, support, and generosity of our little community. Some want to take advantage of that, so let’s have each other’s backs. Love you all, and stay safe…’

Be careful: The Hollywood star, 52, reached out via his approved Facebook page on Wednesday afternoon after being made aware of various fake accounts and money-making scams created in his name

Bankable star: Robert has made his name in a string of blockbusters, including director Guy Ritchie’s 2009 film Sherlock Holmes (pictured)

Fans quickly rallied round, with many claiming they had been approached by scammers masquerading as the Sherlock Holmes and Iron Man star.

Exasperated Facebook follower Charina Russo wrote: ‘I’m glad this is being acknowledged. My messenger has been flooded with RDJ imposters for the past month.

‘What these idiots aren’t aware of is that one can click and peruse on the prof page to see that it’s fake. People like that seriously need real hobbies…..or Jesus. Just get some help.’

Elsewhere Stuart Bernard warned: ‘There’s a lot of online impersonations going on. You have to check the page & profile. No posts , no friends , no pictures dating back years equals a scam artist.

‘Check first before you accept anything . Be a skeptic when it comes to certain things online.’

Reflecting on the growing trend for impersonators, Lisa Kennedy added: ‘I see them all the time and I report them. I wish I could do more but I’m just a little fish in a big pond.’

Goodwill: Roberts associated charities and causes include the ALS Association, the Entertainment Industry Foundation and the Make-A-Wish Foundation

Robert reached out to fans as he continues to reprise his hugely popular roles as Tony Stark and Iron Man in a yet to be named Avengers film.

Filming began in August at Pinewood Atlanta Studios in Fayette County, Georgia.

It is shooting back-to-back with Avengers: Infinity War, with filming scheduled to last until December 2017.

It is intended to be the direct sequel to 2018’s Avengers: Infinity War and has a tentative release date of May 3, 2019.