The 16-year-old who shot five classmates...used an unregistered, untraceable "ghost gun" assembled by hand from various parts, according to Los Angeles County Sheriff Alex Villanueva..."Congress and state legislatures enact all these crimes about gun registration but now the gun industry is creating a way to just bypass the entire thing by creating a mechanism to manufacture weapons yourself," Villanueva said...Thomas Gronenan, detective sergeant with the Suffolk County Police Department in New York, said. “It’s scary..."