Two men with handguns in their waistbands alarmed shoppers when they entered a Kansas City-area Walmart on Sunday, but police say they were just buying ammunition for target practice.

Kansas City, Missouri, Police Sgt. Jake Becchina says the men were cooperative and were released because they hadn’t violated Missouri law.

Shopper Clennon Jones said he saw officers speed into the parking lot and one jumped out with shotgun in hand. Jones says shoppers streamed out of the store and warned others not to enter.

Missouri does not require a permit to openly carry a firearm for those 19 years or older. The Walmart store the men entered does not prohibit guns in the store.

Earlier this month, 22 people were killed during a mass shooting at another Walmart in El Paso, Texas.

Since then, there have been a number of incidents at Walmart stores around the country. Last week, prosecutors charged a 20-year-old man with making a terrorist threat after he walked into a Springfield, Missouri, Walmart wearing body armor, carrying a loaded rifle and handgun, and filming himself with a phone.