Verizon said it made a mistake by not removing data restrictions on a California fire department’s wireless service after firefighters went over their data cap as they struggled to contain the state’s largest wildfire in its history.

In a sworn statement filed this week as part of a legal effort to restore net neutrality rules, Santa Clara County Fire Chief Anthony Bowden said Verizon throttled the connection to one of its emergency response vehicles, which “severely interfered” with its ability to effectively function.

Bowden said the vehicle’s data speed was drastically reduced even as the department grappled with the Mendocino Complex Fire, which has burned more than 350,000 acres. Even though the department alerted Verizon of the emergency, he said the company did not restore its high-speed wireless service because of the limitations of the department’s data plan.

“Verizon representatives confirmed the throttling, but, rather than restoring us to an essential data transfer speed, they indicated that County Fire would have to switch to a new data plan at more than twice the cost, and they would only remove throttling after we contacted the Department that handles billing and switched to the new data plan.”

Verizon said Wednesday that it made a customer support mistake with the fire department and should have lifted the data speed restrictions during the emergency.

“This situation has nothing to do with net neutrality or the current proceeding in court.

“We made a mistake in how we communicated with our customer about the terms of its plan. Like all customers, fire departments choose service plans that are best for them. …

“Regardless of the plan emergency responders choose, we have a practice to remove data speed restrictions when contacted in emergency situations. We have done that many times. … In this situation, we should have lifted the speed restriction when our customer reached out to us. This was a customer support mistake. We are reviewing the situation and will fix any issues going forward.”