PASCO COUNTY, Fla. -- There have been three threats against schools -- R.B. Stewart Middle, John Long Middle and Ridgewood High -- in the past five days, according to the Pasco Sherif's Office.

Sheriff Chris Nocco and a school representative are scheduled to address the cases in a press conference at noon.

The case at John Long Middle School was last week and resulted in the arrest of two teen students who tried to recruit others to "shoot up the school." Another student was arrested Thursday after he posted online he was going to shoot up the school.

Deputies are interviewing two students from R.B. Stewart Middle in Zephyrhills. Late Wednesday, deputies began investigating unsubstantiated rumors being circulated on social media alleging "two students" were planning violence. Investigators worked through the night to identify the source and subjects of the rumors. The students have not been charged.

There will be an increased law enforcement presence at the school on Thursday.

Nocco also will talk about the case of a 9-year-old girl who was followed home by two teenagers.