A teenager accused in August of plotting a Columbine-style attack on Ardmore High School, including the deaths of teachers, students and others, has been indicted on charges of making a terrorist threat and possession of pornographic material, records show.

A Limestone County grand jury recently found adequate evidence to prosecute Andrew Justin Potts, 16, of 26790 Sixth St., on the two charges, which he will face as an adult.

He was arrested at 9 a.m. Tuesday and remained in the Limestone County jail Wednesday night in lieu of an $18,000 bond, according to the Limestone County Sheriff’s Department.

His arraignment date – the day he will enter a plea on the charges – has not yet been scheduled.

Ardmore Police said Potts tried to recruit a former friend to help him carry out an attack on the school like the 1999 assault on Columbine High School in Littleton, Colo., in which two disgruntled students killed 12 fellow students and a teacher.

Potts – who lived with his grandmother – was first arrested at home Aug. 1 after Ardmore Police found a journal the teenager started in 2006 – titled “Book of Hate,” which described impaling people with swords and slashing their throats, police said.

The teenager – who dropped out before school ended in May – had a list of the teachers and students he planned to kill, including teachers, students, the school resource officer and the morning traffic officer, said Ardmore Police Chief William “Doc” Oliver. He told investigators some boys at school had mistreated him.

Ardmore Sgt. Tracy Luna said investigators recovered drawings depicting killings, complete with pools of blood. Police said he also allegedly planned to burn alive a teacher.

Confiscated from the home was a computer containing child pornography, five swords, plans for the school attack and violent movies such as the “Saw” series, police said.

The former friend, whom Potts allegedly tried to recruit to help with the attack and to obtain a gun, said the plot called for attacking as many as three teachers and eight students. The former friend told Potts’ mother of the plan and she reported it to authorities, police said.

After his initial arrest, Potts was banned from all Limestone County Schools property for a year, a duration school board members can extend.

Potts has been charged previously with striking his grandmother, Oliver said.