Dunwoody Elementary School was briefly locked down Nov. 14 due to a threat that turned out to be a hoax sent from the U.K., according to police.

The Dunwoody Police Department on Nov. 13 learned of a social media posting in which someone was “threatening to shoot up his school in Dunwoody, GA,” and alerted the DeKalb County School District, according to police and school officials.

Officials locked down Dunwoody Elementary, at 1923 Womack Road, for less than 20 minutes to make sure it was safe, according to a DeKalb Schools spokesperson.

“Until we could gather facts of the investigation, the school was placed on a very brief lockdown, whereby all students remained in the building with all doors monitored and secured,” said the school district in a written statement. “[School district] police did confirm that a full investigation was conducted and that there is not an immediate threat to the school.”

In a post on the website Nextdoor, Dunwoody Police Sgt. Robert Parsons said the department investigated the threat and discovered it came from an internet address in the U.K. The same address was used to post similar threats throughout the U.S. and Canada, he said.

“At this time, we are confident there is no credible threat in Dunwoody,” Parsons said in the Nextdoor post.

Dyana Bagby is a staff writer for Rough Draft Atlanta, Reporter Newspapers, and Atlanta Intown.