FBI agents served Alexander Paffendorf after discovering he was in contact with 15-year-old Natalie “Samantha” Rupnow, the shooter, and coordinating an attack at a local government building. 

“During an FBI interview, Paffendorf admitted to the FBI agents that he told Rupnow that he would arm himself with explosives and a gun and that he would target a government building,” said the two-page restraining order from the Carlsbad Police Department.

The order additionally said FBI agents “saw the messages from Paffendorf to Rupnow.”

At this time, it is unclear what the nature of the relationship between Rupnow and Paffendorf was.

Paffendorf was served with civil action, not a criminal charge, but authorities can still use this to seize weapons. A San Diego judge approved the order Tuesday, which requires Paffendorf to surrender any firearms and ammunition and prohibits him from getting more.

After the judge signed the order, Paffendorf’s neighbors in California saw more than a dozen police cars enter his apartment complex, according to CBS 8, which originally reported his detainment. 

“They had their full guns out all over the street,” neighbor Alex Gallegos told the outlet. “There were cop cars. I’d say about 15 cops here.”

The FBI said the Madison Police Department is now handling the investigation.

Paffendorf’s gun violence protective order comes just two days after Rupnow opened fire in a classroom and killed one teacher and one student, leaving six others injured, with two still in critical condition.

A court hearing for Paffendorf is scheduled for Jan. 3.