Harry Potter author JK Rowling has blasted a Christian “prayer and lobby group” who blamed Tom Daley’s Olympics failure on his sexual orientation.

Tom said he was “truly heartbroken” after he failed to qualify for the 10m platform final at the Rio Olympics.

But a Twitter account called Christian Voice goaded him: “Turning gay doesn’t seem to have done Tom Daley any favours.”

Tom revealed in 2013 that he was in a relationship with a guy.

Referring to Tom’s fiance Dustin Lance Black, the group added that Tom “only went gay because he was seduced by an older man”.

JK hit back, writing:

She also expressed her sympathy for his disappointment, retweeting comments in support of the 22-year-old diver.

Britain's Tom Daley competes during the men's 10-meter platform diving semi-final Britain’s Tom Daley competes during the men’s 10-meter platform diving semi-final (Wong Maye-E/AP)