A man from the United States was one of eight people detained after tragedy chanting at Sunday's Premier League match between Liverpool and Manchester United, police have said.
The 28-year-old, from Tennessee, was arrested at Anfield under Section 5 of the Public Order Act (Tragedy Chanting) along with a 46-year-old man from Nottinghamshire.
Five other men, aged from 21 to 59, and a 52-year-old woman have been asked to voluntarily attend interviews under caution, on suspicion of the same offence.
Ch Insp Lisa Ledder, of Merseyside Police, said tragedy chanting caused "huge distress to families and people directly affected" and had "absolutely no place in football".