Washington (CNN) The FBI failed to act on a tip about Nikolas Cruz, the confessed shooter in the Parkland, Florida, school massacre, the bureau said in a statement on Friday.

A person close to Cruz contacted the FBI on January 5 to report concerns about him, the FBI said in a statement Friday. But the bureau did not appropriately follow established protocols in following up on the tip.

"The information was not provided to the Miami Field Office, and no further investigation was conducted at that time," the statement said.

The stunning admission -- which prompted Florida Gov. Rick Scott to call on FBI Director Christopher Wray to resign -- is sure to raise further questions about whether the FBI could have prevented the shooting at Marjory Stoneman Douglas High School, which left 17 dead.

The FBI said the caller provided 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 information should have been assessed as a "potential threat to life," the bureau said.

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