Four England rugby players are being investigated by police after a “serious allegation” was made against them in the aftermath of their match against New Zealand.

The incident allegedly took place in a private room at the Hilton Hotel in Auckland in the early hours of Sunday morning after the defeat to the All Blacks on Saturday night.

Auckland police would not confirm last night whether the person who made the allegation was female.

Noreen Hegarty, of the Auckland Criminal Investigation Bureau, said that she could not provide details of the allegation other than that it was serious. No formal complaint had been made and that unless someone was able to corroborate the allegation, it could “end up going nowhere”.

Management at the Hilton Hotel in the city’s waterfront have been interviewed by police. They did not comment last night. However, the England team management confirmed that they had been contacted by Auckland police.

In a brief statement today, Rob Andrew, the RFU elite director of rugby, confirmed England are fully co-operating with police in the matter. "The England rugby team has been informed by Auckland Police that an allegation has been made against four members of the England playing squad," Andrew said. "Whilst no formal complaint has been made we are co-operating with the police and their enquiries.

"The players concerned have the complete support of all the players and the management. In the circumstances we are unable to make any further comment."

A spokesman for Auckland police added: "Auckland City Criminal Investigation Branch is investigating an allegation involving up to four members of the England rugby team. The incident being investigated is alleged to have occurred early on Sunday, June 15, in a private room.

"Whilst an allegation was brought to the attention of police on Sunday evening, no formal complaint has been received. Investigating officers are receiving the appropriate level of co-operation from the England rugby team management."

Richard Prescott, the England team’s media manager, said last night: “The England rugby team has been informed by Auckland police that an allegation has been made against four members of the England playing squad. Whilst no formal complaint has been made, we are co-operating with the police in their enquiries.”

The 32-man England squad had arrived in Auckland on June 4. The alleged incident happened after the team lost to the All Blacks 20-37 in the first Test match of the tour at Eden Park. The team then flew to Christchurch, where they are due to play the second Test on Saturday.

Ms Hegarty said that police had not sought to speak with the England players directly but had been liaising with the squad’s management. She said: “We’ll see how the investigation progresses in the next couple of days.”

It is believed to be the first time that England rugby players have been investigated by police while on tour.