An early morning fire damaged the popular Bob's Big Boy restaurant in the Mapunapuna area today.

Fire Capt. Robert Main said the fire was reported at 2:49 a.m. and brought under control at 3:36 a.m.

Main said firefighters had to cut through the building's roof to gain access to portions of the fire, which appeared to be centered in the restaurant's kitchen area and the exhaust duct work above.

Fire damage was limited primarily to the kitchen although much of the restaurant sustained heavy smoke damage, Main said.

No one was in the building at the time of the fire, Main said. It closed for the night at midnight and the last employee left about 1 a.m., Main said.

A fire inspector was at the scene this morning trying to determine the origin and cause of the blaze, which was battled by about 36 firefighters.

An initial estimate set damages at $1 million to the structure and $500,000 to the contents.

Main said it is likely the restaurant will be closed "for quite a while" while the kitchen and dining areas are overhauled.

Meanwhile, the causes of two fires yesterday have been determined.

A fire at 5:48 p.m. in a bathroom of a home at 3341 Smith Circle was deliberately set and did about $10,000 damage to the structure and $500 to the contents, Main said.

An 8:50 p.m. fire in a house at 1343 Heulu St. in Makiki was cause by an unattended candle left burning in one of the rooms, Main said.

Damage was estimated at $130,000 to the structure and $20,000 to the contents.