Four men accused of pack raping a woman at Mt Maunganui 16 years ago today denied charges relating to the alleged incident during the opening of their trial in the High Court in Wellington.

Court orders prevent the identification of the accused men, now aged between 40 and 53, or their past and present occupations.

All four are charged with rape and abduction. Two are also charged with unlawful sexual violation, one of whom has a second charge of both rape and unlawful sexual violation.

The alleged events occurred in January 1989.

The trial before Justice Ronald Young and a jury of eight women and four men is expected to take up to three weeks.

The woman alleges she was pack raped by five men; one of whom has never been identified or charged.

In court today, the men stood without expression looking straight ahead as the charges were read, and entered not guilty pleas to all charges.