More Internet Backbone Cables Cut in California

The latest in a string of attacks on fiber-optic cables in the San Francisco area caused some Internet service outages in the region on Tuesday. The U.S. Federal Bureau of Investigation has been working with local law enforcement officials to identify who might be behind the vandalism.

Since July 6, 2014, fiber-optic cables providing network connectivity have been intentionally severed in at least 11 different locations around the East Bay and South Bay areas of California. The most recent incident affected three cables in the same area, according to the FBI.

Similar vandalism in Arizona in February left a large number of people without Internet access. It also disrupted cellphone, 911, ATM and credit-card processing services in the areas around Phoenix, Flagstaff, Prescott and Sedona. In that case, investigators suspected perpetrators looking for copper wire to sell on the scrap metal market sliced through the cable using power tools.

Services Restored by the Next Day

Greg Wuthrich, a special agent with the San Francisco division of the FBI, told us the latest cable vandalism in the Bay Area appears related to past attacks in the region. He added that more details will be released later, as investigators are still working to determine which Internet service providers were among those affected.

The affected cables are owned by backbone providers Level 3 Communications and Zayo Group Holdings, which sell capacity to other cable and Internet providers.

A Level 3 spokesperson provided us with the following statement: “On June 30, 2015, the Level 3 network experienced a service disruption due to a fiber cut in the Northern California region. Our network technicians worked to resolve the issue, and all services were restored on July 1, 2015. Level 3 is working with law enforcement as they investigate the fiber cut.”

Attacks Are ‘Concerning’

Tuesday’s vandalism appeared to involve the same methods and patterns as past attacks, Wuthrich said. He called the string of incidents “concerning.” In past attacks, fiber-optic cables have been severed in Berkeley (one incident), Fremont (five separate incidents), Walnut Creek (two incidents), San Jose (one incident) and Alamo (one incident).

Wuthrich said the FBI is urging members of the public — particularly utility maintenance workers who might have been working outdoors nearby — to come forward if they saw anything suspicious in the areas around the vandalism incidents. The FBI has noted in the past that, “The individuals may appear to be normal telecommunications maintenance workers or possess tools consistent with that job role.”

The agency also stated that there doesn’t appear to be any link between the cable vandalism and an April 16, 2013 act of sabotage against a PG&E substation in Metcalf, Calif. In that early morning attack Relevant Products/Services, the perpetrators cut telephone cables in the region and then damaged 17 power transformers with sniper fire. No suspects have yet been arrested in connection with that incident.