Former New Zealand star Mils Muliaina is said to have been arrested on suspicion of sexual assault.
The 34-year-old, who won 100 caps for the All Blacks across an eight-year international career, was led away from the Kingsholm Stadium last night following Connacht's clash against Gloucester Rugby.
Television footage showed Muliani being escorted by police officers in relation to an alleged incident in Cardiff last month.
A spokesperson for Gloucestershire Police said: "A man in his 30s was arrested at Kingsholm Stadium tonight, on suspicion of sexual assault in relation to an incident in Cardiff in March. It is a matter being dealt with by South Wales Police."
Further details are yet to be given, although the alleged incident is thought to have taken place on March 6 when Connacht were in the Welsh capital for a Pro 12 game against Cardiff Blues.
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