ATLANTA (AP) — The FBI director said Thursday that investigators haven’t yet determined a motive behind the mass shooting at a Las Vegas country music festival, but they’re still digging.

“There’s a lot of effort being put into unraveling this horrific act,” Director Christopher Wray told reporters following a ribbon-cutting for the FBI’s new Atlanta building. “We don’t know yet what the motive is, but that’s not for lack of trying, and if you know anything about the bureau we don’t give up easy.”

Authorities have said Stephen Paddock targeted the country music festival the night of Oct. 1, opening fire from the 32nd floor of the Mandalay Bay hotel and killing 58 people.

Wray spent much of his adult life working in Atlanta and said returning for the ribbon-cutting was especially meaningful.

Asked about his relationship with President Donald Trump, Wray said he has very little interaction with the president but is in regular contact with the National Security Council.

“I would describe my relationship with the president as a professional one, and I think that’s what the relationship between any FBI director and any president should be,” Wray said.

The independence of the FBI is extremely important, Wray said, adding that he urges his staff every day to do their jobs professionally and be true to the agency’s core values.

“We can’t be worried about whether there’s somebody somewhere that doesn’t like the fact that we brought a case or we didn’t bring a case or that our intelligence analysis is something people like or don’t like,” he said. “What we have to do is follow the facts independently, wherever they may lead and to whomever they may lead.”STORIES OTHERS ARE CLICKING ON-