Attorney General Jeff Sessions on Friday ordered an “immediate review” of the Department of Justice and FBI after officials failed to follow up on a tip that Nikolas Cruz, who shot up his former Florida high school on Wednesday, could be a threat.

The FBI admitted that "protocols were not followed" in this case, and Sessions said a full inquiry would be made.

“It is now clear that the warning signs were there and tips to the FBI were missed. We see the tragic consequences of those failures,” Sessions said in a statement.

Sessions said he has ordered Deputy Attorney General Rod Rosenstein to conduct an “immediate review of our process” at the Justice Department and FBI “to ensure that we reach the highest level of prompt and effective response to indications of potential violence that come to us.”

“This includes more than just an error review but also a review of how we respond. This will include possible consultation with family members, mental health officials, school officials, and local law enforcement,” the attorney general said.

Sessions called the review a “top priority.”

In the meantime, Sessions reviewed how the department has been helping Parkland, Fla., and the surrounding areas in the wake of the deadly shooting. According to the department, there are 250 FBI staff in both Miami and Washington working on the case.

There are also 17 special agents from the Bureau of Alcohol, Tobacco and Firearms’s Miami office assisting, and 14 more agents from the ATF’s West Palm Beach and Fort Pierce field offices.

ATF has also completed an “urgent trace” of a recovered firearm through its National Tracing Center and is assisting in ballistics analysis, the Department of Justice said.

The Office for Victims of Crime “has funding available to support victim-assistance activities, such as crisis intervention and grief trauma counseling, and to reimburse victims for certain expenses related to the shooting,” and the Office for Victims of Crime and the Bureau of Justice Assistance “stand ready to assist the state and local authorities,” the DOJ said.

According to reports, Cruz — who has reportedly confessed to the shooting — was seen online posing with guns and knives on Instagram. A defense attorney has described him as “a broken child.”