Police discovered a methamphetamine lab inside a Walmart restroom in Muncie, Indiana, on Thursday night. Walmart employees contacted the police around 11:30 p.m. after they discovered a suspicious backpack in the men’s bathroom, according to the Indiana State Police.

When state troopers arrived at the scene, they opened the backpack, where they found an active meth lab inside. Local authorities put on protective gear, which included respirators, and took the lab apart and removed the backpack’s contents from Walmart.

The local health department said that both the men’s and women’s restrooms would be decontaminated before anyone could use them again. The owner of the backpack hasn’t been identified.

“With warm weather approaching and outside activities increasing, so does the potential for people to encounter toxic and hazardous meth trash or a working meth lab left unattended,” the Indiana State Police said in a statement, explaining that those attempting to cook methamphetamines will often leave behind the dangerous and explosive chemicals in warm, public places and return later to pick up the finished product. Meth is a highly addictive and dangerous recreational drug that is frequently popular in small towns.

This means that meth cooks also will frequently dump the trash left over from the process, which can include Liquid Fire drain cleaner bottles, Sudafed, battery casings and drink bottles with white residue in the bathrooms.

“The Indiana State Police Meth Suppression Section wants to remind citizens that these labs and meth lab trash contain chemicals that are toxic, flammable, corrosive and acidic,” the state police added. They also warned anyone who came across suspicious products not to touch them, and to alert authorities instead, since the combination of those chemicals could lead to severe burns and damage skin.