More than a year after a major sniper attack at an electrical substation near San Jose, a new security breach has been reported. 

PG&E officials said burglars stole construction equipment from the Metcalf Substation. The security breach happened at about 2 a.m. Wednesday along a fence line at the station, with burglars cutting through in three locations, reports NBC Bay Area.

The station is currently undergoing upgrades to address security concerns triggered by the sniper attack last April. 

PG&E stressed that the latest security breach did not involve impact to the electrical grid or any electrical equipment, says NBC Bay Area. The company wrote, "the preliminary review suggests human error as the apparent cause of the security breach as fence detection alarms received in security operations were not appropriately addressed."