A suspected cyber attacker targeted the email system used by San Marcos city employees last week leaving them unable to communicate with some of the public.
Employees discovered the problems last Friday morning, and the city manager confirmed they were victims of suspected hacking.
While some public services are delayed, the city manager said emergency services in San Marcos are not at risk.
The attack has forced some residents to make trips to city hall to get help in person for problems they used to solve with email.
"So if emails are coming in, we're not getting them and responding to them. We're not able to email each other, you know, most of the world's business is done through emails these days, so there's a productively issue,” City Manager Jack Griffin said.
The city's computer experts, with help from outside experts, shut down more of the system to keep the damage from spreading.
Things like building permit processing, city council paperwork, finances and accounting are impacted. City officials said the "System will be restored soon" and government files are "Secure and uncompromised."
Attacks like this one aren’t rare, according to a local cyber security expert
"Unfortunately, it's very common,” SDSU cyber security expert Jacob Doiron said. “Just in 2018 alone, there's a little over 10 billion attacks for ransomware. Each attack could have been a single device or an entire network. But it's a fair bit."
The city of San Marcos hopes to have email and internal communications working again in a few days, but not before doing a thorough check on system security.
“We'll do the full-on debrief, and then figure out whatever we have to do to harden things up,” Griffin said.
The fire department's response is not compromised because emergency calls are handled by a separate dispatch system, according to Griffin. And the San Diego County Sheriff's Department, which handles law enforcement for San Marcos, also has its own dispatch system.