Honolulu police are investigating a fire at a Kapiolani Boulevard karaoke bar early Saturday morning, after a fire investigator determined the blaze was intentionally set.

Honolulu Fire Department spokesman Capt. Terry Seelig said the fire at the entrance to Club Geisha House at 1035 Kapiolani Boulevard broke out at about 4 a.m.

Firefighters arrived by 4:06 a.m., brought the fire under control at 4:13 a.m. and extinguished it by 4:18 a.m.

Damage was confined to the entrance of the club.

Seelig said the bar was closed and no one was inside when the fire began.

Firefighters forced open the door of the bar to make sure that the fire had not spread and ventilated smoke from the inside of the club.

Damage is estimated at $3,000.