Following the tragic massacre of 49 people at Pulse gay nightclub Sunday in Orlando, Fla., federal agencies have been investigating whether or not the shooter, Omar Mateen, had connections to terrorist organizations overseas. The CIA announced Monday that they have not found any "direct link" between Mateen and foreign terrorist groups, according to the Associated Press.

Suspicions regarding Mateen's possible ties to terrorist groups abroad were raised in relation to the 911 call he made prior to the mass shooting, in which he professed his allegiance to several radical terrorist groups including ISIS. ISIS also claimed responsibility for the attack as news of the shooting unfolded.

The Associated Press reported CIA Director John Brennan said, at this point in the investigation, the CIA has "not been able to uncover any direct link" between 29-year-old Mateen and any foreign terrorist organization. The remarks were made during a Senate Intelligence Committee hearing on Thursday.

US District Attorney for Florida's middle district, Lee Bentley said Wednesday:

We're working with our law enforcement partners to find out everything that we can about what happened at the Pulse nightclub. We are using all law enforcement and legal tools to reconstruct not only the events of that night but the events of the past several months.

The FBI is still questioning Mateen's second wife, Noor Salman, who drove Mateen to Pulse and claims she attempted to talk her husband out of committing the mass shooting. The Associated Press reported law enforcement is preparing evidence about Salman's involvement in the crime in order to present it to a grand jury.