Mark Halsey has complained to Greater Manchester Police over abusive messages directed against both him and family members via Twitter.
Tweets published after the official sent Jonjo Shelvey off, then gave Manchester United a penalty and denied the Liverpool's own claims for a spot-kick raised the throat cancer Halsey suffered in 2009.
Speaking to the BBC he said: "I can confirm that my family have made a complaint to the police.
"I will be speaking to the police on Wednesday after I have returned from refereeing Southampton v Sheffield Wednesday."
The match officials' union, Prospect, emphasised that the remarks - which involved two Twitter accounts - may have been minimal in number but were unacceptable.
Alan Leighton, the national secretary, said: "Prospect wholeheartedly condemns the unacceptable abuse aimed at Mark Halsey on Twitter. The comments made by a very small minority will be seen as beneath contempt by all decent people. The main concern now is for Mark and his family, who are receiving the support of his employer, PGMOL (Professional Game Match Officials Limited). Prospect will also provide any assistance as required."
PGMOL made a statement which reads: "PGMOL abhors any abuse of match officials whether that is in stadia or outside of it. Our main concern is towards Mark and his family, and as with all match officials, there is a backroom team who are there for them. This includes a sports psychologist, who has worked extensively with the Select Group including Mark over the past few years.
"Mark has already benefited from the support of all of his Select Group colleagues and they will continue to back him this week."
The FA are not expected to take any action against Manchester United despite their fans making offensive chants after the final whistle.
Only a minority of visiting supporters were involved and the governing body recognises that both the Old Trafford club and Liverpool took extensive steps to discourage fans engaging in such actions.
Provocation came from home followers.
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