Spotlight: Orlando nightclub massacre 176th mass shooting in past 168 days in U.S.

The shooting massacre at a nightclub on Sunday in Orlando, Florida was the 176th mass shooting which happened in the United States in the past 168 days so far in 2016, according to the group Mass Shooting Tracker.

Unlike the Federal Bureau of Investigation, which defines the "mass shooting" as an incident where four or more people are killed in one case, the Tracker broadens the definition of the "mass shooting" to include all incidents involving four or more people being shot but not necessarily killed.

By that criteria, the Tracker reports after collecting data from news reports around the nation that the shooting carnage at Pulse, a popular LGBT nightclub, which left 50 dead, including the gunman, was the 176th mass shooting so far this year.

According to the Tracker, as of Tuesday, six more mass shootings occurred in the wake of Orlando nightclub massacre.

At least 49 people were killed and 53 others wounded, including a police officer, early Sunday morning in a shooting spree at a popular LGBT nightclub in Orlando, Florida. It was the deadliest terror attack in the history since the 9/11 terror attacks in 2001.

The gunman, identified by authorities as Omar Mateen of Port St. Lucie, Florida, was found dead inside the nightclub after a shootout with the police.

So far, federal investigators had found no clear evidence that Mateen had been in touch with any terrorist groups before the attack.

However, according to Director of Federal Bureau of Investigation (FBI) James Comey, the authorities were "highly confident" that Mateen had been radicalized online.

Just like his previous reactions after similar mass shooting incidents in the past, U.S. President Barack Obama this time again stressed the importance of passing stricter gun control laws on every public appearances in the wake of the incident.

His latest response came on Thursday during his visit to families of victims and survivors in Orlando, Florida.

"Those who were killed and injured here were gunned down by a single killer with a powerful assault weapon," Obama told reporters. "The motives of this killer may have been different than the mass killers in Aurora, or Newtown. But the instruments of death were so similar. Now another 49 innocent people are dead. Another 53 are injured. Some are still fighting for their lives."

"I truly hope that senators rise to the moment and do the right thing. We can stop some tragedies. We can save some lives. If we don't act, we will keep seeing more massacres like this," he added.

According to federal investigators, Mateen earlier this month legally purchased an assault rifle and a handgun, with which he appeared to launch his mass killing without external instruction.

Though assault-style weapons were banned in 1994, the U.S. Congress refused to renew the ban when the prohibition expired in 2004. Gun-rights advocates argued that rifles of any type were scarcely used in homicides in the country.

Following the 2012 school shootings in Newtown, Connecticut, which claimed 28 lives, including 20 children, the Obama administration initiated but failed to push stronger gun control laws.

The laws, whose sections included expanded background checks and bans on assault weapons, were stymied in Congress after staunch opposition from Republican lawmakers and gun-rights lobby groups.

During his presidency, Obama has been confronted with more than a dozen of high-profile mass shootings, and in an interview last year he called the failure to reform U.S. gun laws "one of the greatest frustrations" of his presidency.

"If you ask me where has been the one area where I feel that I've been most frustrated and most stymied, it is the fact that the United States of America is the one advanced nation on Earth in which we do not have sufficient common-sense gun safety laws, even in the face of repeated mass killings," Obama told BBC in July, 2015. Enditem