An early-morning fire yesterday caused an estimated $3 million in damage to a Hawaiian Cement plant building in Pu'unene, Maui firefighters said.

The cause of the fire at the building, at 10-400 Mokulele Highway, was under investigation.

Firefighters got to the blaze about 4:12 a.m. It was extinguished by 7 a.m. It took six fire units to put out the flames.

The fire burned two 8-by-20 foot containers and a structure that housed a conveyer belt and electrical equipment.