The email sent to Holy Trinity parents Thursday about Friday's modified lockdown includes the day's safety measures including keeping kids indoors, securing all entrances, and having an off-duty officer at the school.
What isn't clear is why the school is on lockdown.
Principal Audra Meyer says the school simply can't offer many more details.
"Since the situation involves a minor and the Des Moines Police are assisting us, we ask that all inquiries are directed to the Des Moines Police Department," said Meyer.
Both Meyer and the Des Moines Police Department confirmed the reason for the lockdown is a domestic dispute involving a family with kids in the school.
The decision to lockdown is a precaution, not a response to any present danger.
"There is no credible threat to Holy Trinity. We don't have any charges or any criminal prosecution against anyone associated with that school,” said Sergeant Jason Halifax, Public Information Officer for the Des Moines Police Department.
School officials say about 80% of the school's 480 students attended Friday and those who didn't were excused.
The same rules will be in effect next week and an off-duty officer will remain at the school if the lockdown continues.
Police say the decision to end or continue to lockdown will be up to Holy Trinity Catholic School, and not the department.