WAILUKU — Hawaiian Cement officials hope a $5,000 reward will help capture whoever used a Caterpillar front-end loader to "wreak havoc" at the company's quarry and cement-making plant in Pu'unene.

"The damage is extensive," said Mike Coad, vice president of Hawaiian Cement. "We're estimating $3 million."

The heavy equipment, which is owned by Hawaiian Cement, was used to knock over large vehicles, punch holes in buildings and attempt to knock over the plant's motor control center, which supplies power to the facility, Coad said.

The vandalism led to a fire that caused further damage, he said.

Coad estimated that it might have taken 30 to 45 minutes for the vandals to inflict the damage.

"You wonder what would drive a person to do this," he said.

Cleanup work at the Pu'unene facility continues, Coad said, and some workers have been reassigned to a second quarry in Waikapu.

Overall, Hawaiian Cement employs 55 people — a dozen in the quarry, 27 in concrete operations (including cement truck drivers) and the remainder in maintenance, quality control and administrative positions.

Replacement parts for equipment at the Pu'unene site are on order from the Mainland, he said. Most cleanup and repair work is being done by Hawaiian Cement employees.

Hawaiian Cement, which is running advertisements of its $5,000 reward, has hired private investigator Matt Levi to look into the case.

Officials from the federal Mine Safety and Health Administration came to Maui to investigate the fire, which was reported at 4 a.m. on Sept. 6. The federal agency has jurisdiction over quarries and mines.

The fire burned two 8-by-20-foot containers, a conveyor belt and electrical equipment, Maui fire officials said. It was extinguished three hours after being reported.

Coad said a special investigator for the agency has returned to the Mainland, but Hawaiian Cement remains in contact with him.

He said the company continues to produce and deliver ready-mix concrete, with no interruption of service.