This story was updated at 11:22 p.m.
Teachers at Ooltewah High School told the Times Free Press that more than half of the school's students -- between 800 and 900 -- are absent today following threats of a shooting.
The school's attendance clerk would not confirm how many students are absent.
On both Friday and Monday threats were written on a bathroom wall, and many parents said they are concerned with how school leaders are handling the threats.
Despite school officials saying there would be increased security at the school today, Matt Lea, spokesman for the Hamilton County Sheriff's Office, said he had no updates about increased security at the school, or what, if any precautions are in place.
The Chattanooga Police Department was never contacted directly by the school about the threats, but said they plan to be involved by increasing patrol in the area.
Kyle Miller, spokesman for the Chattanooga Police Department said the police chief and command staff were in contact with the Hamilton County Sheriff's Office who said police assistance would not be needed today.
Ooltewah High School Principal Jim Jarvis sent an email to parents of students Monday night informing them of the two additional threats of a shooting found at the school Monday.
"At this time neither school officials nor the local law enforcement officials place any validity to the threats," Jarvis wrote in the email. "However, as previously planned, Ooltewah High School will have additional police presence on campus and in our buildings on Tuesday, March 1st."
Jarvis continued to say that Tuesday will be a regular school day "and we will continue to be involved in the business of educating students."
Photos sent to the Chattanooga Times Free Press purport to show a message scrawled on the wall of the boys bathroom, threatening to "shoot up the school" on March 1.
Another message said: "I told you to keep your lips shut I'm done telling my plans."