The search continued Monday for vandals who targeted four power substations on Christmas Day in Pierce County, Washington, setting fire to at least one of the facilities and knocking out power to more than 14,000 utility customers, authorities said.
Two of the break-ins were at Tacoma Public Utilities substations and two others were at a Puget Sound Energy station, according to the sheriff's office in Pierce County, which encompasses Tacoma.
No arrests have been announced.
The vandalism came amid a string of similar sabotage incidents across the country, including several in the Northwest, and follows a bulletin issued last month by the U.S. Department of Homeland Security warning that critical infrastructure could be among the targets of possible attacks by "lone offenders and small groups motivated by a range of ideological beliefs and/or personal grievances."
"It is unknown if there are any motives or if this was a coordinated attack on the power systems," the Pierce County Sheriff's Office said in a statement.
The substation attacks unfolded Sunday between 2:39 a.m. and 7:21 p.m. local time, authorities said. In all four episodes, the saboteurs broke into the fenced-off power stations and deliberately damaged equipment, according to the sheriff's office.
Officials initially said three power stations were vandalized, but early Monday morning they said a fourth substation was damaged in a deliberately caused fire near the city of Graham, cutting power to homes in Kapowsin and Graham.
"The suspect(s) gained access to the fenced area and vandalized the equipment which caused the fire," the sheriff's office said in a statement. "All law enforcement agencies in the county have been notified of the incidents and will be monitoring power substations in their area."
Power was restored to most customers affected by the attacks by Monday morning, the sheriff's office said.
Tacoma Public Utilities reported about 7,300 customers in the southeast of Tacoma were affected by the vandalism. Puget Sound Energy said nearly 7,700 of its customers lost power.
Power was restored to all customers by Monday afternoon, Puget Sound Energy said. Tacoma Public Utilities said later Monday night that all customers were back online but to be prepared for possible outages amid windy conditions overnight.
"Unfortunately, the impacts to our system from today's deliberate damage are more severe in some places than initial testing indicated," the company said Sunday. "Some customers will be restored closer to 8 AM tomorrow. We appreciate your patience as we respond to this intentional vandalism to our system."
"We know this incident has impacted many people’s holiday celebrations, and our crews are working hard to get power safely restored to all customers as quickly as we can," it added.
Earlier this month, two electrical substations were shot up in North Carolina, causing tens of thousands of customers to lose power and prompting local officials to declare a state of emergency. No one was arrested in the attacks.
4 power substations vandalized in Washington state, over 14K lost power originally appeared on abcnews.go.com