Source: Telegraph
Martin O'Neill faces FA charges after Aston Villa's defeat to Manchester United
Villa had led 2-1 at one stage but lost the match 3-2 after conceding a late goal when 17-year-old Federico Macheda scored a stoppage-time winner.
O'Neill later claimed Riley missed a foul on Ashley Young in the build-up to Macheda's goal.
He said after the match: "The officials also got three offside decisions wrong when we were clean through."
The FA have confirmed that the charge relates to O'Neill's behaviour in the immediate aftermath of the match, rather than his critical comments.
The Northern Irishman marched onto the pitch at the final whistle to confront Riley, and it is that action which has landed the Villa boss in trouble with the authorities.
He has until Monday, April 27 to respond to the FA's charge.
