Full coverage: 50 Dead in Orlando Nightclub Shooting

The Orlando shooting has again pushed the gun rights controversy to the forefront of US public debate. Reports say the shooter Omar Mateen had purchased his weapon legally just last week, before he unleashed horror at the nightclub. In the US, shootings occur every single day. And every year, more than 30 thousand people lose their life to guns. CCTV brings you a special report on the fierce debate on gun rights -- this is part one of "a nation at gunpoint".

The nation is greatly divided in attitudes towards the weapon.

The number of guns in public hands is astonishing, making it one of most serious social threats in the United States.

Hosko was in charge of the FBI Criminal Investigative Division.

According to data from the US Centers for Disease Control and Prevention, more than 33 thousand US citizens were shot dead in 2013. Among them, 30 percent murdered, 60 percent commited suicide.

The Brady Campaign is the biggest American nonprofit organization to advocate gun control. It says, from 2009 to 2013, each year nearly 110 thousand people were shot. Among them, more than 17 thousand were under the age of 19.... 2,700 of them died.

The Sandy Hook Elementary School shooting in 2012.... 20 children aged between 6 and 7 years old, as well as six adult staff, dead. The tragedy triggered mass debate on gun rights. The mass shootings didn't stop there, polarizing society even more.

Kristin Goss is a professor at Duke University. She's also the co-author of the book "The Gun Debate".

It's an issue that's spoken of time and again, in presidential press conferences, and presidential candidate debates.

Though Democrats like President Obama say 90 percent of Americans want stricter background checks on buying and selling guns. Republicans have generally put up strong opposition.

According to the US Bureau of Alcohol, Tobacco, Firearms and Explosives, from 2003 to 2013, the domestic production of guns grew steadily. In 2013 alone -- more than 10 million guns. Gun shops are the readily available legal route to obtain a firearm. In 2012, there were more than 50 thousand gun retail stores. That's more than all Subway, McDonald and Starbucks branches combined. Most Americans can find one within a ten minute drive.

Here's a regular gun shop in Virginia.

Shop assistant Mark is always occupied with customers.

US law requires buyers to be a US citizen or permanent resident. Gun shops must also run checks on the customer.

Indoor shooting ranges attract many including veterans.

The NRA -- the National Rifle Association -- is the US's biggest nonprofit organization advocating for gun rights. In the next episode, we'll tell you more about the organization, and the controversial Second Amendment of the US constitution.