A sudden spike in the sales of U.S. firearms has followed fears of tight gun control, after the deadliest mass shooting in recent U.S. history.

Hence, while Smith & Wesson Holding Corp's shares shot up to as much as 11.6 percent, Sturm Ruger & Co Inc hiked by 10.7 percent.

The spike followed the Orlando nightclub shooting, when Omar Mateen, pledging loyalty to the Islamic State, massacred 50 people during a gay pride procession on early Sunday.

He carried an AR-15 style rifle, an assault-style rifle that has killed hundreds in the past. Six months ago, in San Bernardino, Calif., a couple shot 14 people and wounded 20 at a party. In 2012, another gunman killed 12 and injured 58 in a movie theater in Aurora, Colo. In Newtown Conn., a man killed 28 and wounded two at an elementary school.

President Barack Obama had previously slammed the Congress for inaction on gun control. Even earlier in January, after President Obama declared that he would use executive powers to increase the background checks of buyers as well as the licensing requirements for dealers, sales just shot up.

"President Obama has actually been the best salesman for firearms," Brian W. Ruttenbur, an analyst with BB&T Capital Markets, a financial services firm, concluded last month.

Al-Qaeda calls on its followers to take advantage of the arms available. "America is absolutely awash with easily obtainable firearms," American-born al-Qaeda spokesman Adam Gadahn said in a video. "You can go down to a gun show at the local convention center and come away with a fully automatic assault rifle, without a background check, and most likely without having to show an identification card. So what are you waiting for?"

The debates over American gun laws as well as security to control the U.S. presidential campaign between Democrat Hillary Clinton and Republican Donald Trump are expected to get stronger.

While several gun shop owners and managers declared that they had not seen any increase in gun sales after Sunday's shooting, BB&T Capital Markets analyst Brian Ruttenbur confirmed that media coverage and the behavior of politicians were spurring the brisk sales of army style rifles.

"The dynamic shows a Catch-22 for gun control proponents: Pushing for new restrictions can lead to an influx of new guns," said nytimes.

This year, consumer demand had decreased, but could pick up after the recent buying momentum following the shooting.

As CNBC explains: "Smith & Wesson shares were up 6.6 percent at $22.82 in late afternoon trading, while Sturm Ruger's shares were up 8.3 percent at $62.16.

'Up to Friday's close, Smith & Wesson's stock had risen 39 percent in the past 12 months, while Sturm Ruger's shares had risen about 6 percent."