Update at 4:13 p.m.
The shelter in place order is officially lifted, but officials are still warning people who are feeling symptoms to go to the nearest emergency center.
A shelter in place has been issued after a chemical leak at a warehouse in West Harris County. Officials say the leak started last night at a 99 Cents Only distribution center on Colonial Parkway just west of the Grand Parkway and north of Interstate 10 in the Katy area.
Officials say Anhydrous Ammonia is leaking from a refrigeration line that is hard to access. It started last night during routine maintenance and has now escaped the building. Ammonia gas is explosive and officials have asked the areas around the warehouse to shelter in place until the leak is contained.
The areas within the shelter in place boundary include Kingsland Boulevard between Highway 99 and South Mason Road to the south, Mason Road from Kingsland Boulevard North to Mason Creek to the east, Mason Creek between Highway 99 and North Mason Road to the North and Highway 99 between Kingsland Boulevard and Mason Creek to the west.
Local emergency officials say if you're in those areas, you should stay inside with your pets and wait until you get an all-clear notification from authorities.
Anhydrous Ammonia gas is colorless, but has a distinct pungent odor. It is most often used in agriculture, but is sometimes used for refrigeration purposes as well. Usually stored as a liquid under pressure, it becomes a toxic gas when released into the environment.