An 18-year-old student has been arrested on suspicion of attempted murder after he allegedly threatened to carry out a "Columbine" type massacre at his Orlando high school next year.

Lake Brantley High School student Emmanuel Costas was arrested Tuesday after posting multiple threats on Facebook and in text messages that he was going to carry out violence against other students.

"It was clear he planned on carrying out this attack in the school lunch room," Altamonte Springs police chief Michael Deal said. "He admitted to sending these texts and he admitted to posting similar [messages on his] Facebook page. During his interview, he also made disturbing comments that he respected individuals that carried out the Columbine massacre."

Investigators released transcripts of the text messages on Wednesday afternoon. One message read, "Everybody prepare yourselfs 4/17 let the carnage begin," while another read, "A day of terror will strike upon everyone's soul."

Two days after these texts were received, a third message was sent which read, "Damn 4/17/12 is going to be a day to remember dat day will bring joy to me and sadness to OTHERS."

Police say they also recovered papers from Costas' backpack and his home, which also documented his threats to carrying out a mass shooting at the school.

Costas was charged with attempted felony murder and written threats to kill or do bodily harm. He is being held without bond at the John E. Polk Correctional Facility, about 25 miles northeast of Orlando.

Costas' older sister told myFOXorlando that she did not believe her brother was capable of carrying out a Columbine-style act. "No not at all. He's not that type of person," she said. "He just thought it was funny and stuff like that."

Twelve students and one teacher were shot dead by senior students Eric Harris and Dylan Klebold at Columbine High School in Colorado in 1999. The pair, who had earlier made threats online about their violent plans, shot themselves before being caught by police.

To read more on this story, see myFOXorlando.com