A threat of violence against Oxford High School which drew response from several Oakland County Sheriff’s deputies as a precaution late Thursday morning turned out to be bogus, officials said.

The call came in at around 11:45 a.m., claiming a person was in the bathroom with an AK-47-type automatic rifle and a pipe bond, threatening to shoot everyone and detonate the bomb. The school was placed on lockdown and the building was searched out of “an abundance of caution,” the sheriff’s office said.

Nothing of concern was found during the search and students were sent home early, the sheriff’s office said.

Prior to the all-clear, the sheriff’s office said the threat was believed to be not credible but, to be on the safe side, was still taken seriously. In a news release issued by the sheriff’s office, Sheriff Michael Bouchard stated: “Every threat will be fully investigated, and we will always seek to hold the responsible accountable. We have even worked with partners in Europe to prosecute people in the past.”

The sheriff’s office said the threat came from the Netherlands, and is believed to be “swatting.”