Investigators are still trying to piece together the motive that caused Stephen Paddock to carry out the most deadly shooting in American history.

Mysteries are still surrounding the case.

But a Las Vegas sheriff revealed a secret that points in one disturbing direction.

Clark County Sheriff Joseph Lombardo met the press on Tuesday to provide a further update on the investigation.

There have been questions as to the shooter’s motivation.

Was this an act of terrorism?

Or was he a madman who snapped?

Sheriff Lombardo dropped a tantalizing clue when he was asked if the shooter had been radicalized by someone unknown to law enforcement.

The Daily Caller reports:

“Clark County Sheriff Joseph Lombardo gave a press conference Tuesday and responded to questions whether Las Vegas shooter Stephen Paddock had been “radicalized.”

Speaking to reporters, Lombardo said, “I want to understand the motivation that you described, okay, to prevent any future incidents, and, you know, did this person get radicalized unbeknownst to us? And we want to identify that source.”

The sheriff’s remarks reignited fears that ISIS was involved in the massacre.

After the attack, ISIS’ official news agency issued four tweets claiming credit for the shooting.

Investigators will continue to probe into whether Paddock was radicalized and by whom.

He does not fit the profile – ISIS recruits are often younger men who are second generation immigrants – but that should not rule out the possibility he was inspired by ISIS or converted to their ideology without anyone knowing.

We will keep you up to date on any new developments in this case.