HOUSTON — The North American subsidiary of a French chemical manufacturer and two senior staff members have been indicted in connection with last year's explosion at the Crosby, Texas, plant in the wake of Hurricane Harvey.

Arkema North America, its CEO Richard Rowe and plant manager Leslie Comardelle were charged in Friday's Harris County indictment with "recklessly" releasing chemicals into the air. The charge carries up to $1 million in fines and five years' imprisonment.

After Arkema's plant lost power, its organic peroxides began heating and decomposing. The compounds, used in products including plastics to paints, caught fire and partially exploded, sending plumes of smoke skyward.

First responders and neighbors said they were sickened after the incident.

Arkema spokeswoman Janet Smith on Friday said the corporation would fight the indictment.