LEHIGH ACRES, Fla. -- Two Florida middle schoolers with an apparent interest in the Columbine High School massacre were allegedly plotting to carry out a school shooting of their own until a teacher was tipped off about a possible concealed weapon, authorities said.
The teacher at Harns Marsh Middle School in Lehigh Acres, near Fort Myers, alerted school administrators and a school resource officer about the tip from students Wednesday, authorities said. A search of an eighth grader's backpack did not turn up a gun, but administrators allegedly found a map that "contains markings indicating the location of each of the school's interior cameras," Lee County Sheriff Carmine Marceno said during a press briefing Thursday afternoon.
An investigation by the office's youth services criminal investigations division ultimately identified two students -- a 13-year-old and a 14-year-old -- "involved in a plot to carry out a school shooting," Marceno said.
The pair were "extensively studying" the 1999 Columbine High School shooting -- in which two teens killed 13 people -- and attempting to learn how to construct pipe bombs, the sheriff said.
Searches of their homes allegedly found "disturbing evidence, including a gun and several knives," he said.
"This could have turned disastrous," Marceno said. "We were one second away from a Columbine here."
The sheriff also likened the foiled plot to the "next Parkland massacre" -- the 2018 school shooting in which a teen fatally shot 17 people at a high school in Parkland, Florida. "But we stopped them in the planning stages," he said.
The two students, who were both known to authorities as deputies had visited their homes nearly 80 times combined, will be charged with conspiracy to commit a mass shooting, according to the sheriff.
Lee County Superintendent Ken Savage commended the students who came forward to report the potential threat, the teacher who alerted administrators after receiving the tip and the "quick action by our staff."
"Students were safe at all times," Savage told reporters, noting that the classroom was emptied while administrators investigated the threat. "All the threat assessment and emergency response training made a difference in the outcome of this incident."
Both teenagers met the criteria for an evaluation at a mental health facility, and investigators will be looking into a risk protection order, which restricts firearm and ammunition access for those who pose a danger to themselves or others, Marceno said.
Authorities identified the students at the press briefing Thursday, but ABC News is not naming them because they are minors and had yet to be charged.