By CBS3 Staff

UPPER MERION TOWNSHIP, Pa. (CBS) – Flames erupted at a Montgomery County chemical plant early Wednesday morning. Hazmat crews were called to the Coopers Creek Chemical Corporation on the 800 block of River Road in Upper Merion Township, just after 4 a.m.

A lot of dark smoke could be seen coming from the facility.

READ MORE: EXCLUSIVE: Body Of Missing 26-Year-Old Casey Johnston Recovered, Officials Say
Hazmat Team Responds To Fire At Conshohocken Chemical Plant

Coopers Creek Chemical Corporation

Officials tell Eyewitness News the fire started somehow during the processing of crude coal tar. An employee saw the fire and called for help.

READ MORE: Colts' Carson Wentz Choosing Rest, Rehab For Foot Injury, Remains Out Indefinitely

According to the Coopers Creek Chemical Corporation’s website, they refine crude coal tar which is used to make asphalt.

The cause has yet to be determined but officials do not believe it to be suspicious.

MORE NEWS: Philadelphia Fire Crews Battle Junkyard Fire In Port Richmond

The incident remains under investigation.