On Friday a hacker accessed the water treatment computer systems for the city of Oldsmar, Florida, and altered the chemical levels of the water to a dangerous level. News of the attacks was only publicised on 8th February, after Oldsmar city officials held a press conference about the matter.
It appears that the hacker first accessed the computer systems on 5th February at 8am, and then later on in the day at 1:30pm. The first intrusion was only for a short time, while the second intrusion lasted for around 5 minutes. This was when the attack was first detected, as the operator who was monitoring the water facilities systems noticed that their mouse was moving without them doing so.