The Orlando gunman responsible for the largest mass shooting in American history journeyed to Saudi Arabia twice in recent years on pilgrimages to the holy city of Mecca.
Omar Mateen made the trips to the Middle East in March of 2011 and March of 2012, spending 10 days in the country a spokesman for Saudi Arabia's Interior told NBC News.
It was one year after that second trip where he performed Umrah - which is considered the lesser pilgrimage compared the Hajj - that Mateen first landed on the radar of the FBI.
A source close to that investigation has revealed to The Guardian that the agency started looking into Mateen after learning that he told his co-workers that he was friends with Tamerlan and Dzhokhar Tsarnaev, the brothers behind the Boston Marathon bombing.
The FBI interviewed Mateen twice about his comments and ultimately decided he did not pose a security threat because he had been lying about knowing the Tsarnevs.
He became a "known quantity" to federal law enforcement agents after that investigation however, but was still able to legally purchase the guns he used in Sunday's brutal massacre.
Mateen had been looking to purchase military-grade body armor in the weeks prior to the shooting as well according to investigators.
CNN reported that the body armor Mateen had been trying ti purchase was an "even higher level than what ordinary police departments supply to their officers."
The strength of the armor would have likely "allowed him to survive a prolonged shootout with police officers," leading investigators to believe Mateen was very likely planning this attack for weeks and had no intention of committing suicide.
The local store where Mateen attempted to buy the armor refused to sell it to him though when he went to make the purchase just weeks before the attack.
There are still many questions about the shooting and Mateen's motivation, with the young man seeming to undergo a drastic shift in his behaviors and beliefs around the same time he took his 2011 trip to Saudi Arabia.
His first wife Sitora Yusifiy, who he married in 2009 after the two met through an online dating site, said that during their relationship she never saw Mateen show much interest in religion and that he preferred to spend his time working out in the gym.
Mateen "did practice and he had his faith" said Yusifiy, but was not devout or radical about his beliefs.
There was a shift in Mateen though according to Yusifiy, who said that he "loved to joke, loved to have fun" and cared about his family when they first met, but that all changed after their wedding.
"A few months after we were married I saw his instability, I saw his bipolar, and he would get mad out of nowhere, and that's when I started worrying about my safety," said Yusifiy.
"Then after a few months he started abusing me physically, very often, and not allowing me to speak to my family, and keeping me hostage from them."
Yusifiy made the decision to leave Madeen after just four months of marriage, and said her family had to come and pull her out of his arms.
They were not officially divorced however until July of 2011, which was two years after they first separated and just a few months after Madeen returned from his first pilgrimage.
A friend of Madeen's who wished to remain anonymous said in an interview with The Washington Post that he started becoming more and more religious in the wake of his divorce from Yusifiy.
That friend added however that Mateen never said anything or behaved in a way that would lead him to believe he had become radical in his beliefs.
If that is the case it is unclear why Mateen would want to tell his co-workers at G4S Security in Port St. Lucie, Florida that he knew the Tsaranevs.
The FBI would not comment on the investigation but a spokesperson did confirm that Mateen was lying when he claimed to know the two young men.
It was also around this same time that Mateen welcomed a son with Noor Zahi Salman, who was listed as his wife on a September 2013 mortgage.
Little is known of their relationship at this time, and it is not clear if the two were even still together with Salman reportedly living at a different address than Mateen.
If the two did split it would have been recently based on a story being told by Mateen's father Seddique concerning his son's feelings about gay people.
He claims that just a few months ago Mateen became "very angry" when he saw two men kissing in front of his family and young son during a trip to Miami.
Mateen's disdain for homosexuals is a recent development though according to a former classmate who said that he did not have a problem with gay men and women when they were in high school.
Samuel King, who is openly gay and used to perform as a drag queen, said Mateen was friendly, talkative and would often socialize with the may gay people they worked with at Ruby Tuesday's.
"He clearly was not anti-(gay) at least not back then. He did not show any hatred to any of us," said King.
"Something must have changed."