UPDATE: An online threat to "shoot up Bear Valley Elementary" that sent three Anchorage schools into stay-put modes Thursday was false, police said Friday.

The source of the threat, an out-of-state juvenile, was interviewed by the FBI according to police spokesman MJ Thim.

"The juvenile was interviewed by the FBI and it was determined the threat was a hoax," Thim wrote.

FBI spokesman Rich VanVeldhuisen said Friday that the juvenile’s location and identity weren’t being released, pending a decision on whether to charge him with a crime.

“Basically, we determined that the IP address which was used to post the threat was associated with a location outside of Alaska,” VanVeldhuisen said. “The parents allowed authorities to interview the juvenile; he admitted to posting the threat and authorities determined it was a hoax.”

The juvenile didn’t tell investigators whether he was referring to Anchorage’s Bear Valley Elementary in the social-media post, or one of at least two other U.S. schools bearing the same name.

Original story:

An online threat against a school that may or may not be in Alaska prompted Anchorage police to put three schools in stay-put mode Thursday, where two of them remained at midday despite a finding of “no credible threat” by investigators.

The stay-puts, which involve locking exterior but not internal doors, were put in place at Bear Valley Elementary School, as well as Goldenview Middle School and South Anchorage High School according to police spokeswoman Renee Oistad. They were prompted by a message on the FBI’s national tip line, regarding a social-media post in which someone threatened to “shoot up Bear Valley Elementary” before killing himself.

“Out of an abundance of caution, both Bear Valley Elementary and Goldenview Middle School were put into stay-put mode where they remain,” Oistad wrote. “Goldenview was put into stay-put mode due to its proximity to Bear Valley.”

Staff at South High spotted two vehicles which were thought to be suspicious, causing South to also be placed in stay-put until the vehicles were cleared.

Oistad said word of the FBI tip reached police Thursday morning, after the school day had already begun. She emphasized that neither the bureau nor APD believe the threat – which might have referred to at least two “Bear Valley Elementary” schools in other U.S. states – is real.

“We’re still looking into it but we’re not concerned for anyone’s safety,” Oistad said. “We don’t believe anyone is in danger.”

APD school resource officers were sent to Bear Valley, where they will be in contact with the FBI and remain for the rest of the day. Oistad said stay-put modes at that school and Goldenview were likely to continue for the rest of the day as well.