An apparent electrical fire early this morning caused up to $300,000 in damages to a concrete batch-mixing facility on Marshall Road in Cranberry Township.

The blaze shortly before 1 a.m. destroyed the main control and office building at the family-owed John T. Thrower Cement Co. plant.

The 40-by-100-foot building was one of three at the Saxonburg-based company’s secondary operation near Interstate 79 in Cranberry Township.

John T. Thrower Jr., company president, has already vowed to rebuild.

“As soon as possible,” he said.

Only one regular employee works at the facility, Thrower said, ”but there are trucks in and out of there all day.”

Now and for the time being, all loads of ready-mixed concrete, cement and plaster will be hauled out of the company’s main operation in Saxonburg.