Police are investigating threatening text messages sent to the wife of Premier League referee Michael Oliver, the BBC reports.
Oliver awarded a last-minute penalty as Real Madrid knocked Juventus out of the Champions League on Wednesday and was criticised by Italian keeper Gianluigi Buffon and some Italian media.
BBC Sport understands Oliver's wife Lucy - a Women's Super League referee who also officiates men's non-league football - had her mobile number posted on social media after the game, which led to the abusive texts.
Police are also looking into reports of people banging on the front door of the couple's home address and shouting abuse through their letterbox.
Officers have now deactivated the phone number, although Lucy Oliver's social media account has also been targeted by some supporters.
Juventus captain and Italy international Buffon was sent off for confronting Oliver over the 93rd-minute penalty decision.
He later told media the English official had a "bag of rubbish for a heart".
On Saturday, Buffon said he "stands by all of it".