The FBI failed to act on a warning that 19-year-old Nikolas Cruz could carry out a deadly attack on a school, only a month before Wednesday's mass shooting at a Florida high school when a teen gunman killed 17 people, the FBI has admitted.

A person close to Cruz contacted the FBI on January 5 to report "information about Cruz's gun ownership, desire to kill people, erratic behavior and disturbing social media posts, as well as the potential of him conducting a school shooting," the FBI admitted on Friday.

Florida's Republican governor, Rick Scott, an ally of President Donald Trump, said the "FBI's failure to take action against this killer is unacceptable." He called for FBI Director Christopher Wray to resign.

Florida Senator Marco Rubio, another Republican, said Congress should open an investigation into the FBI's failings.

Attorney General Jeff Sessions has ordered a review of what went wrong, with the FBI missing the early warning signs of one of the deadliest mass shootings in US history.

The tip was made to the FBI's hotline, but the information provided by the caller was not forwarded to the FBI field office in Miami, the FBI said.

"Under established protocols, the information provided by the caller should have been assessed as a potential threat to life," the FBI said.

Wray said the agency would be reviewing processes on how the FBI responds to information provided by the public to the hotline, which received more than 2,000 calls a day in 2017.

Other warnings missed

The FBI admission comes as it was revealed that the agency also failed to fully investigate a tip about Cruz last September.

FBI Director Christopher Wray is under pressure over the agency's failure to act on the tips

According to Mississippi resident Ben Bennight, he became concerned when a user named Nikolas Cruz left a comment on his YouTube channel saying "I'm going to be a professional school shooter."

FBI investigators, however, were unable to determine the source of the post.

Warning signs were also missed at the local level. Sheriff Scott Israel of Broward County said Friday that his office had received about 20 calls in the past few years about Cruz, and that his office would be investigating how those calls were handled.

Cruz used an AR-15 rifle to fire more than 100 rounds at students and teachers on Wednesday at Marjory Stoneman Douglas High School, before being arrested off the school campus.

Motive unclear

The 19-year-old was later charged with 17 counts of murder. Investigators have yet to confirm a motive.

Cruz was known to be violent. He had been expelled from the school for fighting with his ex-girlfriend's new boyfriend and for threats to his classmates and teachers. Cruz's public defense attorney said he had a history of mental illness.

Cruz and his brother were living with family friends after the death of their mother in November. Their father died when they were young.

The family friends had allowed Cruz to bring his AR-15 rifle, but had made him lock it up. It was legally purchased, authorities said.

Claims that surfaced on Thursday of Cruz's connections to the white nationalist group Republic of Florida have so far not been verified by law enforcement officials. The leader of the group, Jordan Jereb, made the claims in interviews with various news organizations.



Watch video 01:56 Trump addresses Florida shooting

Trump visits victims

US President Donald Trump met with victims at a Florida hospital on Friday, saying it was "very sad that something like that could happen."

Accompanied by his wife, Melania, Trump thanked doctors, nurses and medical staff for their "incredible" work.

Trump is expected to meet with law enforcement officials later in the day.

cw, tj/ng (AFP, AP, dpa, Reuters)

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