Now playing Next USA Texas church massacre Gunman walks into church and opens fire on the congregation in a small town in Texas 06/11/2017
Now playing Next USA Gunman 'killed himself' after Texas church massacre Gunman walks into church and opens fire on the congregation in small town. 06/11/2017
Now playing Next Germany German police hunt gunman after supermarket shooting Witnesses have described hearing an argument before shots were fired. 02/11/2017
Now playing Next USA Three people killed in a shooting in Colorado Three people were killed in a shooting at a Walmart store in Thornton, Colorado on Wednesday. 02/11/2017
Now playing Next USA Eight people dead after truck-ramming terror attack in New York Donald Trump ordered the Department of Homeland Security to "step up" vetting measures following the attack 01/11/2017
Now playing Next USA Texas student in custody after campus police officer shot dead Texas Tech University in Lubbock was locked down while the suspect was at large. 10/10/2017
Now playing Next USA Euroviews. View: US states should choose gun sanity for themselves Rather than fighting another ill-fated battle in Washington, more states should be encouraged to exercise their prerogatives, writes Jeffrey D. Sachs 09/10/2017
Now playing Next USA Public urged to help solve mystery behind Las Vegas massacre It is still unclear what drove gunman Stephen Paddock to commit mass murder 07/10/2017
Now playing Next world news This week in pictures: Las Vegas tragedy, Catalonia turbulence and PM May's very bad day 06/10/2017
Now playing Next USA Explained: the gun modification that helped make Las Vegas' shooting America's deadliest What are "bump stocks" and how do they work? 06/10/2017
Now playing Next USA Adding debt to injury? Las Vegas survivors set for huge medical bills 05/10/2017
Now playing Next USA Las Vegas gunman rented room overlooking another music festival week before shooting Paddock's girlfriend says she knew nothing about the attack 05/10/2017
Now playing Next USA Las Vegas gunman adapted weapons, set up cameras before premeditated shooting At least 59 people were killed and more than 500 injured in the shooting 03/10/2017
Now playing Next USA Las Vegas massacre: what we know At least 58 people were killed and 489 injured in the Las Vegas shooting 03/10/2017
Now playing Next USA Las Vegas shooting: the victims What we know about the 58 victims of the Las Vegas shooting 03/10/2017
Now playing Next USA Heroism of the Las Vegas concert goers who put others first As bullets rained down, members of the Route 91 festival audience risked their own lives to save others 03/10/2017
Now playing Next USA How did Las Vegas shooter fire so rapidly? Automatic weapons are banned for civilians in the US, but loopholes exist. 03/10/2017
Now playing Next USA Las Vegas shooter owned over 40 guns Gun shop owner said Stephen Paddock had cleared "all necessary background checks and procedures." 03/10/2017
Now playing Next USA How many civilian guns does a well-regulated militia need? America is a historically and culturally different environment to Europe when it comes to the use of firearms by private individuals 02/10/2017