Former All Black Mils Muliaina has been arrested in the United Kingdom after a game he was playing for his Irish club team Connacht.
Muliaina, 34, was pictured being led away from the ground and put in a police van minutes after the match, the Irish Independent reports.
Gloucestershire police say a man in his 30s was arrested at Kingsholm Stadium in relation to an alleged incident in Cardiff in March.
Muliaina will leave Connacht for Italian side Zebre at the end of this season.
Operated by the Italian rugby federation, Zebre play in the Guinness Pro12 and the Heineken Cup.
With 100 caps between 2003 and 2011, the Samoa-born Muliaina stands fifth on the All Blacks appearances list.