California Man Accused of Coordinating Local Plot With Wisconsin School Shooter

Turns out the Wisconsin teen school shooter may have had a partner in crime -- a California man has been detained for allegedly planning a mass shooting at a government building in a coordinated attack with her.

According to a gun violence restraining order obtained by San Diego's CBS 8, 20-year-old Carlsbad resident Alexander Paffendorf is accused of exchanging messages with Natalie Rupnow about opening fire at a local government building ... while she attacked the Abundant Life Christian School in Madison on Monday.

The emergency restraining order from the Carlsbad Police Department states, "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."

The civil order doesn’t specify which building Paffendorf allegedly planned to target, or provide the exact messages he allegedly shared with Rupnow. A San Diego judge approved the restraining order Tuesday night -- hours after the Madison shooting.

The judge approved the order under California’s red flag gun law, requiring Paffendorf to hand over all his guns and ammunition to police within 48 hours, according to a local news station.

Neighbors told CBS 8 more than a dozen police cars swarmed Paffendorf’s home, where officers were seen carrying out a large gun box.

Cops are hoping Paffendorf's alleged exchange with Rupnow will shed light on the teen's motive for the school shooting that left 2 dead and 6 injured, including 2 in critical condition. Rupnow died from a self-inflicted gunshot wound.