The threat of a “shootout” at Centennial High School in Roswell beefed up police presence on campus Wednesday as administrators launched an investigation into the source of the information scrawled on a restroom wall.

The message, discovered Tuesday, warned of violence to come on Thursday.

Fulton County campus police and officers with the Roswell Police Department responded to Centennial High to help with the investigation.

No arrests have been made.

A voicemail from Centennial High principal Steven Miletto alerted parents about the threat: “I’d like to make you aware of a discovery at school. Today, written on a bathroom wall was the following statement: R.I.P. CHS kids 2/16/12. There is going to be a shootout. This is for real."

The message to parents Tuesday evening also told them that school officials were reviewing video footage and interviewing students about the incident. The principal said the threat was being taken seriously.

“We need our students to understand that threats are not a joke,” Miletto said in the recording. “Any threat that hinders your child’s education or jeopardizes our safety will not be tolerated. We are asking for your help in the effort to keep our school safe and disruption free.”

A tips line was provided for those who may have more information to share with authorities about the threat. Parents also were provided with a number to call to discuss their concerns.

Fulton Schools spokeswoman Samantha Evans said the threat did not lead to a dip in attendance Wednesday or result in a flood of phone calls from parents.

“Everything is fine,” Evans said. “We have taken all of the necessary precautions to make sure that students at the school are safe.’’

Evans said Roswell police will likely return on Thursday to assist campus police.