Authorities have released information on an April 16th “military style” attack on a California power substation that has left them “puzzled” and “worried.”

According to Foreign Policy, one or two individuals “cut fiber cables in the area around” the PG&E Metcalf power substation. Afterward, they “entered two different manholes” and fired “100 rounds…from a high-powered rifle” at transformers in the substation.

Ten transformers and three transformer banks were damaged. “Cooling oil then leaked from a transformer bank” and transformers overheated and shut down.

Additionally, the cuts in the fiber cabled knocked out “911 services, landline service to the substation, and cell phone service in the area.”

The attack was originally being handled by local police but was then passed to the FBI due to concerns that it may have been terror-related. The FBI says it has found “no evidence that the attack is related to terrorism.”

Follow AWR Hawkins on Twitter @AWRHawkins.