A man armed with a rifle and 100 rounds of ammunition was arrested at a Walmart store in Missouri on Thursday. The incident comes days after a series of shooting incidents killed dozens in the United States.
Springfield officials said no shots were fired by the suspect and his motives were unclear. He was arrested after he walked out of the store with his weapon.
"An armed white male in his twenties was detained by an armed, off-duty fireman until officers arrived on the scene and took the suspect into custody," the official statement said.
Describing the incident as "really scary, dangerous situation", police told media that they are looking into the suspect's social media pages to determine if he had any threatening motives.
The southern state of Missouri is an "open carry" state which gives people the right to freely carry firearms in public. However, restrictions are imposed on convicted felons.
The recent mass shooting in El Paso, Texas, and at a Dayton bar in Ohio have restarted discussion on gun regulation and violence in the US.
Amnesty International on Wednesday issued a worldwide travel warning and urged "people worldwide to exercise caution and have an emergency contingency plan when travelling throughout the USA".
Calling the issue as a human rights crisis, the group said the advice was "issued in light of ongoing high levels of gun violence in the country".
US President Donald Trump's trip to meet the families and first responders affected in the shootings was met with criticism. Democrat representatives have accused Trump of "inflaming tension with anti-immigrant and racially charged rhetoric".
The gunman in El Paso was deemed to be a white supremacist after it was revealed that he had put up anti-immigrant posts online. The growing discussion on Trump's electoral ideas was also defended by Trump's White House aid, who have said that the gunman of the Dayton shooting ideas endorsed 2020 Democrat candidates Elizabeth Warren and Bernie Sanders.