ATLANTA, Ga. (AP) – The Georgia man who shot at Centers for Disease Control and Prevention buildings on Aug. 8 apparently tried to enter the campus two days earlier but was turned away by security, according to an internal CDC email.

Security video indicates “a very high likelihood” that the 30-year-old shooter — Patrick Joseph White — tried to enter the campus on the late afternoon of Aug. 6, the email said.

“The video evidence does not 100% confirm the person’s identity” but law enforcement thinks it was White, according to the email sent to CDC employees on Thursday.

“The probing of a site is a common practice for individuals planning to engage in violent acts,” Jeff Williams of the CDC’s security office wrote in the email. The Associated Press viewed a copy of the email, which was first reported on by Stat News.

White blamed the COVID-19 vaccine for making him depressed and suicidal. On Aug. 8, he opened fire from a spot at a pharmacy across the street from CDC’s main entrance. He killed a police officer and fired more than 180 shots into CDC buildings before killing himself. No one at CDC was injured.

Williams, in his email, said: “Due to our existing security protocols, the shooter did not attempt to enter campus on Friday, August 8, prior to the attack.”

A spokesperson for the Georgia Bureau of Investigation said the investigation is active and ongoing.

“We have no further information to release at this time,” said the spokesperson, Sara Lue.