By Mike Hellgren

BALTIMORE (WJZ) — The Baltimore City 911 dispatch system was breached Sunday, prompting a temporary shutdown of automated dispatching, according to the mayor’s office.

A spokesperson for Mayor Catherine Pugh said in a statement Tuesday that the breach at 8:30 a.m. affected messaging functions within the system’s Computer Aided Dispatch Network, which supports 911 and public safety emergency services.

Officials say a technician changed some of the firewall security settings while working on an unrelated problem.

The problem was fixed on Monday morning after more than 17 hours and the City says all 911 calls were handled.

Ransomware is a software that blocks access to a computer until you pay up. Investigators are still trying to determine who hacked the system.

911 staff had to manually provide details of emergency calls, including locations, which is normally done electronically.

“We know that there was some sort of limited technological problem with one of the servers that serves the computerated dispatch for the city,” said University of Maryland cyber security expert Ben Yellin. “So until we get answers from the city in terms of exactly what happened, I don’t think we can characterize what happened.”

A recent study by UMBC revealed one quarter of local governments were subject to cyber attacks, sometimes as frequently as once every hour.

Atlanta is still reeling from a computer attack. Last year in Dallas, Texas, someone was able to activate every tornado siren. Other targets include hospitals, an attack on MedStar in Baltimore two years ago, shut down many of their computers while criminals demanded payment in bitcoin.

“Any kind of failure is going to happen,” said Yellin. “The more we can plan for them the better.”

The City has not said what the ransomware attackers were demanding. They do note that no citizen’s private information was compromised.

The FBI is assisting the city in its investigation into the attack.

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