FedEx shooter was known to authorities before tragedy took place: sources

The gunman, who after murdering 8 people committed suicide, was flagged by a family member to law enforcement before the attack took place. Journalist John Cardillo tweeted that "the FBI dropped the ball on another one."

The gunman's identity was released today as 19-year-old Brandon Scott Hole. The motive for this act of violence, however, is so far unclear.

The FedEx facility was located in Indianapolis, Indiana and the suspect has not yet been made public to the press. CNN, however, has reported that the gunman was known to authorities.

Authorities were warned about FedEx suspect’s potential for violence in the past, wrote one CNN journalist on Twitter.

He continued by saying, "the suspect in the Indianapolis mass shooting was known to federal and local authorities prior to the attack."

The gunman opened fire at around 11:00 pm near the city's airport.

"It is very heartbreaking and, you know, in the Indianapolis Metro Police Department, the officers responded, they came in, they went in and they did their job," said a police spokesperson.