MARSHALL — A chemical reaction involving cleaning chemicals at the Archer Daniels Midland plant in Marshall sent three people to the hospital for observation on Thursday, the Marshall Fire Department said.

The fire department and the Southwest Chemical Assessment Team both responded at the plant.

The fire department received a call about the incident around 12:30 Thursday. A reaction involving cleaning chemicals in an employee bathroom at the plant created a gas, said Marshall Fire Chief Quentin Brunsvold. Both the fire department and the Southwest CAT were on the scene for a few hours Thursday afternoon.

Brunsvold said three people were sent to Avera Marshall Medical Center for observation, but he didn’t have further information on their conditions.