Hackers attempt to poison water supply in Florida town

In a cyberattack on Feb. 5, hackers remotely accessed the water treatment plant in Oldsmar, Fla., briefly changing the levels of lye in the drinking water.

According to Pinellas County (Fla.) Sheriff Bob Gualtieri said in a press conference that the level of sodium hydroxide—the main ingredient in drain cleaner— was changed from 100 parts per million to 11,000 parts per million. The breach was caught before in could cause harm.

Authorities reported that an employee noticed someone else was controlling his computer, but dismissed it as the city has software that allows supervisors to access computers remotely. The employee then noticed that different programs were being opened, and the lye levels had been changed. Gualtieri said the intrusion lasted between three and five minutes.

Oldsmar has disabled remote access, according to City Manager Al Braithwaite. The investigation is ongoing, with the FBI and U.S. Secret Service being notified.