PRINCE GEORGE'S COUNTY, Md. (WUSA9) -- Students reported a large number of absences at some Prince George’s County Schools Monday as anxious families reacted to a weekend epidemic of social media threats that spread like a contagion in the region.

Elanor Roosevelt High School in Greenbelt canceled all outdoor after school activities and shut down its outdoor classrooms Monday as a precaution.

The property was patrolled throughout the day by extra police officers. Prince George’s County police said they aim to arrest anyone they can link to the threats that appear to be linked to a nationwide epidemic of threats with a so-called “creepy clown” theme.

Afterschool activities have been canceled at Eleanor Roosevelt High School and students have been relocated from temporary classrooms after an online threat was made.

Students returned to classes at Flowers High School in Springdale Monday under heavy police presence due to an online threat that surfaced over the weekend.

RELATED: Additional security on Monday at Prince George's Co. schools after threats

One dad, who did not want to be identified, called in the threat after his son brought it to his attention Saturday.

The posting was about a school shooting at Flowers and Bladensburg High Schools, as well as Kenmoor and William Wirt Middle Schools.

The father sent his son to school with a promise.

“I will be right across the street in case anything happens,” he told his son.

But he was never hesitant to send his son to school saying, “I'm a U.S Marine so I'm not hesitant about anything, I'll tell you that. Not at all, I have full faith and confidence in Prince George's County Police Department to protect our children."

The principal passed out letters to parents, as students walked past the police line to get to class.

Online, students tweeted their frustration with the schools decision to stay open.

“It’s not that I’m completely scared because where we live at but it’s a little weird to come to school with a bunch of police officers like it’s a crime scene,” one student said.

“It’s better to be safe than sorry,” said another student. Police said they take every and all threats seriously.