BALTIMORE (WJZ) — Anne Arundel County Public Schools have announced an increased police presence on campuses this week as a “precaution” following the deadly school shooting in Florida nearly two weeks ago.

The announcement was made two hours before the school system tweeted about a threat made against a county high school Sunday night.

We are aware of an online threat that implies violence at Northeast HS. Police are aggressively investigating leads in the case. If you have any information that could assist in this case, please call police. At this time, we plan to open school as normal tomorrow. — AACPS (@AACountySchools) February 26, 2018

Threats were also made against a county middle school via social media just two days ago. Officials at Lindale Middle School were made aware of the threat Friday, and second period classes were temporarily held. However, the threat was unfounded.

The school system emphasized in a Facebook post Sunday that, at the time, there were no credible threats against any county schools.

Maryland has seen more than 15 school threats in less than two weeks. While in most cases, police found no credible threats, police and schools have been on high-alert.

Baltimore County Police responded to Lansdowne High School on Friday morning after a Snapchat post described the Parkland shooting suspect as a “brother” and promised more victims.

Two Harford County students were charged Friday after police say they wrote a threatening message on a desktop at the school.

Follow @CBSBaltimore on Twitter and like WJZ-TV | CBS Baltimore on Facebook