The shooting massacre 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.

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, US President Barack Obama this time again stressed the importance of passing stricter gun control laws on every public appearance in the wake of the incident.