Reid confirmed yesterday a complaint had been made with the police over an incident in the centre of Dunedin on Friday morning.
Reid said it involved a Highlanders player or players. He declined to name the those involved.
He said the New Zealand Rugby Union and the Highlanders were investigating and were taking the matter "very seriously".
"I am exceedingly disappointed and angry about the continued behaviour of the players," he said.
He declined further comment but said the investigation was continuing.
Police confirmed yesterday they were seeking witnesses to an incident on the corner of lower Stuart St and the lower Octagon at 4.40am last Friday.
Sergeant Sheldon Kindley said police were asking for any witnesses to the assault.
He declined to make any further comment, and would not confirm whether Highlanders players were involved.
The Highlanders have had a blighted off-field record over the past couple of years.
Halfback Jimmy Cowan was convicted on two disorderly behaviour charges last year and placed on an alcohol ban during the season by the NZRU.
Winger Lucky Mulipola was convicted in April last year of driving while disqualified, providing the police with a false name, and assaulting a member of the public, after an incident on April 5.
Loose forward Adam Thomson is facing a charge of assault after an incident in Havelock North last December.
Winger Fetu'u Vainikolo was fined $1000 by the NZRU in February this year after pouring a drink over a woman's head in a Dunedin bar.
