NORTH TEXAS (CBSDFW.COM) – More than 20 cities across the state, including at least one in North Texas, have fallen victim to what officials are saying is a ‘coordinated’ ransomware attack.

According to the Department of Information Resources (DIR), hackers have infected at least 23 municipalities with malicious software. CBS 11 News has learned that the court system, water, police, and fire department computers in the Dallas County city of Wilmer are virtually being held hostage in the attack.

Officials say it was on the morning of August 16 when the locations, mostly smaller local governments, reported the ransomware attack. It’s believed all the attacks came from a single source.

DIR spokesperson Elliott Sprehe said none of the cities have paid the ransom to the hackers. The exact amount they’re asking for isn’t known.

State authorities have brought in more than a dozen cyber-security experts — including workers from the FBI, FEMA, Texas Emergency Management, Texas Military Department, the Texas A&M Security Operations Center/Critical Incident Response Team and DPS — to help get the systems back online.

Exactly what data or services have been compromised isn’t known, since officials haven’t said how many computers were breached.