San Jose and three other U.S. cities on Wednesday sued the Justice Department and Bureau of Alcohol, Tobacco, Firearms and Explosives for failing to regulate the sale of "ghost guns" amid a rise in violent incidents tied to the untraceable firearms, which can be built in just hours using online kits.

The lawsuit, filed in Manhattan federal court, accused the agencies of "arbitrarily" excluding key parts for the guns from their enforcement of the Gun Control Act and allowing gun-building kits without serial numbers to be sold unchecked.