Wray added, "It's up to all Americans to be vigilant, and when members of the public contact us with concerns, we must act properly and quickly".
US Senator Marco Rubio also criticized the FBI separately, saying it was "inexcusable" the FBI did not follow protocols. An FBI agent confirmed a field officer in Jackson, Mississippi, received the tip and interviewed the person who shared it.
The agency's admission comes after it emerged on Friday another report was made to the FBI last September regarding Cruz.
If a tip appears credible and warrants further investigation, it is supposed to be forwarded to an FBI field office. We see the tragic consequences of those failures.
Photo A young girl and a woman embrace as they leave a funeral service for Alyssa Alhadeff.
"We will make this a top priority. All of us will be forever changed". Our children's lives depend on it.
The governor called for the FBI director to resign.
"I just want people to stop, like, talking about it and then not doing anything", she said. The information should have been assessed as a "potential threat to life", the bureau said.
The FBI said it investigated that comment but was unable to trace its origins, closing the inquiry until Cruz surfaced in connection with Wednesday's shooting.
"I'm going to be a professional school shooter", the comment said. Many schools, including Marjory Stoneman Douglas High, run annual drills in which students practise huddling in classrooms behind locked doors.
During a Friday news briefing, Lasky apologized that protocol wasn't followed for the January tip.
The friend took her phone to the principal, who found the Auburndale police school resource officer.
What do we know about the suspect?One of the attorneys said Cruz's had the mental state of a "child".
In addition to his teaching duties, Beigel was the school's cross country coach.
Fred Guttenberg, whose daughter Jaime Guttenberg was killed, spoke at the vigil.
Ethel Guttenberg said her granddaughter was a competitive dancer and that orange was her favorite color.
Onetime neighbor Shelby Spano said Nikolas Cruz once threw eggs at her husband's car.
But of course the United States has a drinking age of 21, meaning that a teenager can legally arm himself with enough weaponry to kill 17 at Marjory Stoneman Douglas High School, but to drink one can of beer is breaking the law.