TEXAS CITY (AP) — An explosion and fire struck a refinery in Southeast Texas, home to the biggest concentration of petrochemical plants in the country.

The blast shook the Valero refinery in Texas City just before 5 p.m. Wednesday. Flames flared about 100 feet into the air and a column of black smoke towered over Galveston Bay.

Valero officials reported that all of its personnel were accounted for with no injuries among them.

City officials said there were no effects to the general public outside the plant, beyond advising motorists to avoid the area. No cause has been reported for the fire, but it was unclear if it would affect the plant’s output.