NBC chairman blasts Donald Trump in private Facebook post

US: Chairman of NBC Entertainment, Roberts Greenblatt has blasted US Republican presidential candidate Donald Trump, refereeing to him as "toxic" and "demented" in a private Facebook post that went public on Monday.

Greenblatt's post refers to a "sad state of affairs thanks to a business mogul" who thinks that airing his mind is "refreshing".

The executive chairman in a Facebook on Monday said;

"It's actually corrosive and toxic because his 'mind' is so demented; and his effect will unfortunately linger long after he's been told to get off the stage," (didn't mention Trump by name).

Greenblatt's Facebook post also ridicules the network's one time "Apprentice" star, ratings prowess, stating that Trump's show "consistently ran behind in its time period, by the way."

"The Apprentice," became a hit for NBC when it began airing in 2004 but the latest season finale of "Celebrity Apprentice," the most recent incarnation, finished in fourth place when it aired in February 2015, behind shows such as "ABC's "The Bachelor" and CBS' "Two Broke Girls."