The Brief Seattle police said Tuesday they recovered a "ghost gun" at the scene of the Bite of Seattle shooting that left three people dead and five injured. These types of weapons are referred to as "ghost guns" because they do not contain serial numbers, which makes them difficult to track. At a Tuesday news conference, Seattle police said they recovered a "ghost gun" along with two other guns at the scene of Sunday's deadly Bite of Seattle shooting. Keep reading to learn more about ghost guns and how they are manufactured. What is a ghost gun?