Three days after a social media threat forced a brief lockdown at Dunwoody Elementary, threats continue to be made against other schools in the city.

None of the threats were determined credible, but the schools have been placed on varying levels of lockdown while they are investigated. Threats came in to Vanderlyn, Austin and Kingsley elementary schools Friday, prompting lockdowns.

“We have every reason to believe right now that all these incidents are the result of someone ‘swatting,’ someone actively putting these fake threats out there trying to get a response, trying to cause panic and harm to the community,” Sgt. Robert Parsons said in a Facebook Live broadcast from Austin Elementary Friday.  “And that’s exactly what’s happened.”

When police were made aware of the first social media threat to “shoot up” a Dunwoody school Tuesday, they launched a full investigation with the help of DeKalb County school police.

The series of posts came from an IP address outside the United States that was used to send several similar messages threatening schools in Canada and elsewhere, Parsons said.

“At this time, we are confident there is no credible threat in Dunwoody,” police said Wednesday.

MORE: Cops: Threat to 'shoot up' DeKalb elementary school came from outside U.S., was not credible

During the initial investigation, Dunwoody Elementary was placed on brief lockdown, and nearby Austin Elementary was under a low-level lockdown as a precaution.

On Thursday, Dunwoody Elementary received another call threatening the school, and the school was placed on the highest level of lockdown. Police remained on campus through dismissal, the school district told Channel 2 Action News.

The threatening calls and social media posts have continued. Parsons said investigators are working with federal authorities to determine where they are coming from and if the calls and posts are connected.

Although police presence has been heightened at Dunwoody schools the past several days, Parsons reiterated investigators do not believe the threats are credible and said fear and panic is “the last thing we want.”

“We are doing everything we can to track down these perpetrators and find out who is making these disgusting threats,” he said. “This is obviously not something that we are going to take lightly. This is not a joke.”

Social media threats were also made against schools in Clayton County on Friday and are heightening security presence on campuses and surrounding areas, school authorities told Channel 2.

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