Authorities in Washington state were asking for surveillance or other video Tuesday as they investigate what has been called deliberate damage to power substations.

The vandalism at four substations south and southeast of Tacoma on Christmas Day left more than 14,000 customers without power, officials said.

The Pierce County Sheriff’s Office said equipment was damaged at two Tacoma Public Utilities substations and two Puget Sound Energy substations, all of which was discovered or occurred Sunday.

The sheriff’s department has said a reason for the burglaries and vandalism incidents, one of which caused a fire, was unknown.

“It is unknown if there are any motives or if this was a coordinated attack on the power systems,” the department said Sunday.

Sheriff’s department spokesman Sgt. Darren Moss Jr. did not release any more details about the investigation Tuesday but said “We are working with and notifying all law enforcement partners in the region.”

He said that the damage to the substations was not caused by a firearm, but did not specify how it was caused.

The sheriff’s department asked Tuesday on social media that anyone with surveillance video at their home or business review the video.

The FBI in Seattle said that it was aware of the reports but that it does not confirm or deny the existence of an investigation.

“We routinely share information with our local partners and take threats against our infrastructure seriously. We urge anyone with information to contact law enforcement,” the FBI said in an email.

Power has been restored, officials said.

Tacoma Power has said its substations “were deliberately targeted with physical damage.”

The four substations were in the communities of Spanaway, Graham, South Hill and Kapowsin.

The first incident was around 5 a.m., and the last, which involved a fire caused by the vandalism at the Kapowsin station, was around 7:30 p.m., the sheriff’s department said.

In early December in North Carolina, power was cut to thousands of people after someone shot two substations, severely damaging equipment, officials there said. The FBI said it joined the investigation into those incidents, which it called “willful damage.”