Attorney General Jeff Sessions said Thursday that law enforcement "must do better" to prevent mass shootings in the wake of the massacre at a Florida high school.
"It is just too often the case that the perpetrators of these terrible attacks had given of signals in advance," Sessions said in a speech to the Major County Sheriffs' Association.
"We've had advance indications and perhaps we haven't been effective enough in intervening immediately to deal with that. I suspect it appears that we've seen that again in this case."
He told the group of sheriffs gathered in Washington that "we cannot arrest everybody that somebody thinks is dangerous."
"But I think we can and must do better. We owe it to every one of those kids crying outside their school yesterday and all those who never made it out," Sessions said. "Our hearts are hurting today."
The FBI was warned in September about a possible school shooting threat from a YouTube user with the same name as Nikolas Cruz -- the 19-year-old who allegedly opened fire at Marjory Stoneman Douglas High School in Parkland, Florida, killing at 17 people -- according to a video blogger. It was one of at least two alleged threat reports about the suspected shooter that the FBI received, a law enforcement official told CNN. In both cases, the FBI did not share the information with local law enforcement, the official said.
Sessions said he has directed the Justice Department's legal policy office to work with the various departments across the Trump administration to study the intersection of mental health and criminality. He also vowed that the Justice Department will confront the problem of mass school shootings and make it a "priority."
"It cannot be denied that something dangerous and unhealthy is happening," Sessions said in his speech. "When parents, once again, go to sleep in fear that their kids will not be safe when they leave for their school bus in the morning, we must confront this problem. "
He continued, "We are going to take action. We must reverse these trends."