The Walmart Supercenter on Highway 6 and Westpark Drive was evacuated Sunday night after a mystery spray caused a number of customers to choke and sent four to the hospital.
Deputies at the Harris County Sheriff's Office said the incident occurred around 8:45 p.m. From watching the surveillance footage, deputies believe that two suspects in their late teens or early 20s walked into the store and began to spray a chemical from canisters.
The unknown substance caused employees and customers to have a hard time breathing and left a burning sensation in the eyes and throat.
Authorities are unaware what chemical caused the reaction that forced the supercenter to evacuate 100 to 150 customers and employees. The suspects have not been apprehended.
Hazmat crews were sent to the store overnight and cleared it to reopen Monday morning.
Watch the full KHOU Channel 11 report here: