HENRYETTA, Oklahoma - Employees returned to work at the Anchor Glass plant in Henryetta after an explosion and fire Wednesday night.

Some workers said they were nervous to walk inside the building and see considerable damage to the plant.

One representative said employees are spending the day cleaning up and doing damage assessments, but they're not sure when it'll be back up and running at its full capacity.

One man said he was driving by, saw the explosion Wednesday night and stopped to watch it. He said his father-in-law left his job at the plant last week, so he was thankful he wasn't hurt.

We also heard from plant workers who saw the damage for the first time Thursday morning.

"It could've happened again while I'm in there, so, I guess it was just good luck I wasn't in there," plant worker Christian Zorichak said.

We've reached out to Anchor Glass corporate staff for a statement but we are waiting to hear back.

According to Henryetta Fire Chief David Bullard, the explosion is still under investigation but said it like started because an oil line ruptured in the basement.

Bullard said there were employees in the basement at the time but wasn’t sure how many.