When the first reports of multiple fires in California’s Sonoma County poured in Sunday night, emergency dispatchers were at the same time sending out fire crews to investigate downed PG&E power lines and exploding electrical transformers in the area, the East Bay Times reports. Personnel were reportedly sent out to at least 10 locations over a 90-minute period to look into sparking wires and other electrical-system problems. San Francisco-based utility PG&E and others in the state have been in the past found responsible for major destructive wildfires over power-line maintenance issues. The utility released a statement Tuesday night acknowledging the equipment issues over the weekend in Sonoma—reportedly caused by high “hurricane-strength” winds—but noted that any broader questions about maintenance issues causing the area’s wildfires are at this point “highly speculative.” In April, PG&E was fined $8.3 million for a power-line maintenance problem that caused the September 2015 Butte Fire in Amador County. State fire officials are still investigating the cause of the Wine Country blazes, which are only 40 percent contained. The wildfires ravaging the area have killed at least 21 people and destroyed more than 2,000 homes in multiple counties.