MASSENA -- Smelting operations at both the East and West Alcoa plants are continuing as normal despite a major fire that spread to the roof of the Casthouse Thursday.

At the same, an investigation is underway in an attempt to determine the cause of the blaze, that could be seen from throughout much of Massena.

Under the direction of fire officials, molds used to cast molten metal have been moved from the casthouse to the smelter and employees have successfully been pouring molten metal into the molds, said Laurie Marr, Alcoa Communications & Public Affairs Manager, in a prepared statement late this afternoon.

She said the operations are expected to continue.

A preliminary survey of the casthouse today determined areas that are structurally safe, she said. This allowed state fire investigators to begin their investigation.

“It is too soon to determine the extent of damage to equipment and the long-term impact on processes,” said Marr. “It is unknown how long the investigation process will take.”

She said Alcoa officials are in the “early stages” of investigating the incident, and teams from Alcoa and local and state authorities are on scene to help with the assessments.

Alcoa has received “tremendous offerings of support from our community and employees,” she noted.

The fire started at about 3:10 p.m. Thursday and appears to have started in the chip melter, where aluminum chips are melted, but the cause is still under investigation.

All employees were evacuated safely.

Numerous local fire departments responded to the scene, along with Alcoa's own fire brigade.

The fire spread to the roof of the Casthouse and the burning of the roof contributed greatly to the smoke that was visible throughout the Massena area.

The local fire departments were dismissed from the scene late Thursday night and early this morning.

The East Plant was not impacted by the fire, said Marr.

She said Alcoa is working with its customers “to make sure their needs are met.”

View slideshow of photos of the fire.