Iron Man star Robert Downey Jr has apologised to fans after his Instagram account was hacked.

The Hollywood actor's 43.2 million followers were left confused after posts offering free iPhones and Apple Watches appeared on his story.

Downey Jr's Instagram biography was also briefly edited so that fans who clicked through arrived at a form asking for personal information.

The posts - which suggested fans could also claim free PlayStations, Amazon gift cards and Tesla Model X cars - were deleted after several hours.

On Twitter, the 54-year-old warned fans to avoid his Instagram page for the time being.

He said: "I'm sorry to say my Instagram has been compromised... Please steer clear for the time being until it's sorted. Thank you all. I love you 3000."

The unknown hacker would have also had access to Downey Jr's private messages and pictures.

Downey Jr is best known for playing the tech-savvy superhero Tony Stark in the Marvel Cinematic Universe film franchise.

Fictional billionaire playboy Stark is characterised as an engineer and hacker.

Both Love Island star Curtis Pritchard and US actor Dylan Sprouse, from The Suite Life of Zack & Cody, have also been targeted by hackers this year.

More  movie news, reviews and interviews here