The director of a new documentary about US singer Michael Jackson has labelled some of the online reaction to it as "disgusting".

'Leaving Neverland' is a two-part documentary about two men, who recount their experiences of being sexually abused by Jackson.

James Safechuck, at age 10, and Wade Robson, at age seven, were both befriended by Jackson.

"They and their families were entranced by the singer's fairy-tale existence as his career reached its peak", Channel 4 said in its description of the programme.

The two men, now aged in their 30s, speak out in the documentary - as well as their mothers, wives and siblings.

HBO aired the first installment of the documentary on Sunday night in the US.

Director Dan Reed told Sean Moncrieff: "They were star-struck and they were taken in and they adopted him almost like a son.

"He groomed the mom's, is the fact, and they felt he was like a son to them and they loved him like a son.

"And then, of course, behind their backs he was having sex with the little boys."

"He would pick families that had a flaw... and usually where there was some tension between mom and dad and where he could become the focus of attention for the child."

"And the transition to sexual - from affection, to touching to a sexual relationship - was kind of like, as Wade says, it felt completely natural".

Reed explained why he made the programme: "Well I didn't believe them straight away.

"I met James and Wade and then interviewed them for day after day after day.

"I think I interviewed Wade for three day and James for two.

"Then I went off and tried to corroborate everything I could, and then I did a deep-dive into the police investigations around Jackson.

"I didn't find anything that contradicted even a small detail of anything the guys had told me".

Reed also hit out at online critics to the documentary: "It's disgusting, its vitriolic - the first response seems to be to slime these young men, to pour scorn on them as victims of sexual abuse.

"I can't think of any other situation in which your first reaction would be to basically try and beat up someone who says they have been raped.

"It's completely unacceptable".

Tom Porter, Channel 4 commissioning editor, said: "Dan Reed has succeeded in making an extraordinarily compelling, yet moving film about two men whose lives were changed forever by one of the most famous men who ever lived.

"Channel 4 is immensely proud to have commissioned this film and created the opportunity for James' and Wade's experiences to be so sensitively told."

Part one of the documentary is set to air on Channel 4 this Wednesday March 6th at 9.00pm.

Listen to Dan Reed's full interview below:

Main image: Michael Jackson is seen in a still from 'Leaving Neverland' | Image: Channel 4