Eells, whose police career spanned nearly 30 years, said in one scenario a fire started when tear gas interacted with Scotchgard furniture spray on a couch and spread to the drapes. Most recently, police in Victoria, B.C., say tactical officers arrested a person who had barricaded themselves in an apartment on Christmas evening 2019. The firefighters extinguished the blaze while tactical officers moved in, and the suspect was taken to hospital in critical condition. Police said they threw a common form of tear gas known as CS — an acronym for Ben Corson and Roger Stoughton, the two U.S. chemists who first synthesized the chemical compound in 1928. The tear gas forced the 34-year-old and another individual, a 50-year-old woman, to exit the building.