Black Diamond Nightclub must close two hours earlier to reduce early-morning trouble at the Waikiki Trade Center, the Honolulu Liquor Commission ruled yesterday.

Jeffrey Ko, the club owner's brother, said he was shocked by the decision and that he will appeal. He said the club received permission to stay open until 4 a.m. in February. Since opening the club last May, the owners had planned to operate late, and the decision will leave them bankrupt, Ko said.

The commission is looking at whether two other clubs—the Shack Waikiki and Zanzabar—at the Trade Center also should close at 2 a.m. instead of 4 a.m. because the number of incidents at the center has not decreased despite additional security measures, said acting Administrator Anna Hirai.

Black Diamond was hit with the restriction because the registered owner was not present to defend the club.

The commission will continue the hearing for the Shack Waikiki and Zanzabar to July 8.