VOLGA, S.D. (AP) — A Brandon man is dead after an explosion at a soybean plant in Volga.

The Brookings County Sheriff's Office says the blast happened Thursday afternoon at the South Dakota Soybean Processing plant as workers were installing catwalk structures to access the tops of storage tanks.

Thirty-nine-year-old welder Randy Satter was working at the top of a tank when it exploded, killing him.

The cause of the explosion was not immediately determined.

The federal Bureau of Alcohol, Tobacco, Firearms and Explosives, the state Fire Marshal's Office and the state Division of Criminal Investigation are helping in the investigation.

Copyright 2015 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.