WASHINGTON (AP) — The Justice Department's inspector general is conducting a four-city examination into storefront undercover operations run by the Bureau of Alcohol, Tobacco, Firearms and Explosives to assess whether they pose a danger to the public.

The ATF runs sting operations in various cities, often as part of an effort to catch arms traffickers who bring stolen weapons into storefronts where agents act as buyers.

The IG's office said Thursday it is looking into storefront operations in Milwaukee, Pensacola, Fla., St. Louis, Mo., and Wichita, Kan.

IG Michael Horowitz said if his office learns of information that might warrant looking at additional storefront operations, it will consider expanding the review to include them.

The ATF ran a Milwaukee storefront operation intended to bust felons for drug and gun offenses, but the Milwaukee Journal Sentinel reported in January 2013 that no major drug dealers or gang members were taken down. The store was robbed of $35,000 in merchandise, an agent's machine gun was stolen and a document listing undercover agents was left behind.

The ATF store opened in Milwaukee in early 2012 as Fearless Distributing. It offered designer clothes, athletic shoes, jewelry and drug paraphernalia for sale.