STOCKTON — Vaporized mustard gas was detected leaking from a bulk container at the Deseret Chemical Depot on Tuesday.

The gas, the depot reported, was detected during routine monitoring operations in a storage igloo.

Depot workers used specialized equipment to contain the vapor, then moved the agent-filled munition to another storage structure. Workers in protective clothing will clean the crystallized agent residue from the outside of the container and replace the valves later this week.

The igloo is covered by earth, and the air inside is filtered. No vapor escaped into the environment and there was no danger to the surrounding community, a news release said.