Two suspicious incidents, as well as rumors spread in the halls, have prompted more law enforcement presence and staff supervision at Hilton Head Island High School this week.

Principal Amanda O'Nan said students have circulated all sorts of rumors -- about a homicide on Hilton Head last Wednesday; the Newtown, Conn., school shooting; and a message scrawled on a bathroom wall Monday that prompted tighter security and a Beaufort County Sheriff's Office investigation.

"It's a lot of rumor control," she said, "but at the same time, you can't let your guard down or take things lightly. You spend a lot of time and resources trying to get to the bottom of it."

Two Sheriff's Office reports released Wednesday detail separate incidents Monday.

At about 10:45 a.m., assistant principal Sandra Jensen said she heard gunshots coming from the direction of Gumtree Road when she was outside the building, according to a report. No evidence of shots fired was found and no one interviewed -- including about 30 people at the nearby Island Recreation Center -- heard shots, according to the report.

Then, a threatening message was found in a boy's restroom.

According to a report, someone wrote, "Today at around 1:20 p.m. there will be a shooting at this school. I overheard a conversation, and this is a warning. DIE!!!"

The message was discovered by assistant principal Joseph Skirtich and was written so faintly it was barely visible. It was removed from the wall after deputies photographed it.

It's not clear when the message was written, according to the report.

In response, school administrators were assigned areas to patrol, and more deputies were called to the school for the rest of the school day.

The increased law enforcement presence has remained, O'Nan said. Along with the school's regular school resource officer, the Hilton Head Island Middle School resource officer and two or three other deputies have been at the school. O'Nan said they would be in the school today, the last day before winter break.

O'Nan has also asked assistant principals to supervise hallways; a hall monitor will check exterior doors frequently. Teachers have been asked to come earlier than their usual 7:15 a.m. arrival time, to monitor halls during their planning periods and to ensure students leave the building promptly.

The school has not been on lockdown, O'Nan said.

It's the only instance of increased security at a Beaufort County public school this week, school district spokesman Jim Foster said.

O'Nan said any rumors should be reported to teachers or another adult at the school.

"Don't talk to your peers about the rumors," she said. "Report it to adults. ... If I haven't heard it, I can't act on it."

Related content

• Beaufort County School District schools remind parents of security steps; Dec. 17, 2012