The girlfriend of Las Vegas shooter Stephen Paddock, 64, has returned to the United States after traveling abroad. Upon landing at Los Angeles airport, Marilou Danley, 62, was greeted by FBI agents.  

According to the Associated Press, Danley will be questioned about the mass shooting, which resulted in the death of at least 59 people and injured over 500.

Las Vegas Sheriff Joseph Lombardo described Danley as a “person of interest” and said authorities expect “some information from her shortly.” Lombardo also told reporters he is “absolutely” sure they will be able to determine Paddock’s motive.

Although Danley left for the Philippines a little over a week before the Oct. 1 attack, Danley’s relatives say she had no idea what was happening.  

“She didn’t even know that she was going to the Philippines until Steve said, ‘Marilou, I found you a cheap ticket to the Philippines,’” one of her unidentified sisters, who resides in Australia, told NBC’s Australian partner, Channel 7.

“She was sent away," the woman added. "So that she will not be there to interfere with what he’s planning."

Philippines immigration bureau spokesperson Antonette Mangrobang said the local authorities there were fully cooperating with U.S. officials on the case.

“From the very beginning, we have been providing them necessary information that would aid their investigation,” Mangrobang told the Associated Press.

According to authorities, Paddock transferred around $100,000 to the Philippines days before the attack. Investigators determined that Paddock gambled more than $10,000 a day. They are still working to trace the exact location of the $100,000.

Lombardo also said the investigation could result in additional criminal charges being issued for other individuals.  

“This investigation is not ended with the demise of Mr. Paddock,” Lombardo told the Associated Press. “Did this person get radicalized unbeknownst to us? And we want to identify that source.”