At least 60 schools in Michigan closed Thursday, and more than 20 will close Friday following a string of threats following a shooting Tuesday at Oxford High School, near Detroit, where four students were killed.
While authorities expected false threats following the initial incident, Oakland County Sheriff Michael Bouchard said the current number of threats are "completely off the charts," the Detroit News reported.
The department had to call in assistance from the FBI and the Secret Service to assess the claims. "If you're making threats, we're going to find you," Bouchard said.
Several arrests have already been made in relation to the threats.
One 17-year-old high school student in Flint, Mich., was arrested Thursday after she allegedly posted a rap-style video on social media threatening to commit a mass shooting. She faces charges of 20-year felonies including a false threat of terrorism and committing a crime using a computer.
Another 17-year-old in Southfield, Mich., is expected to face charges after allegedly bringing a gun to school Wednesday.
According to police in Southfield, yet another student was found Wednesday with a pistol and bullets.
In Sterling Heights, a girl was arrested after allegedly making threats against a high school.
Students in South Lake High School were evacuated following a bomb threat Thursday.
One 16-year-old student, Bowie Cooper, says, "With the COVID-19 pandemic, I feel like I’m never going to have a normal year of high school."
Bouchard said he expects schools to reopen Monday. "We're assigning extra people to be in those buildings and to reassure students and parents and that's not going to stop. What we need to do is come together, not get more torn apart," he said.
The eight people who were injured in the Tuesday attack are still recovering.
The suspected Oxford High School shooter, Ethan Crumbley, 15, will be charged as an adult. The prosecutor has not ruled out charging his parents.