Utah’s South Jordan Police Department announced on Wednesday that the National Highway Traffic Safety Administration has sent a team to investigate a crash involving a Tesla Model S with Autopilot engaged. The driver, a 28-year-old woman from Lehi in Utah, admitted that she had been looking at her phone before the collision even though the feature requires users to remain alert at all times.

The crash occurred May 11 at 6:38 p.m. Mountain time, when the Tesla collided with a mechanic truck from the Unified Fire Authority, with both drivers receiving minor injuries. Analysis by Tesla showed the driver repeatedly cancelled and re-engaged the Autosteer and Traffic Aware Cruise Control functions, adjusting the cruise control speed throughout and taking her hands off the wheel more than a dozen times, only holding her hands there for a few seconds each time. Around a minute and 22 seconds before the crash she re-enabled both features and took her hands off the wheel two seconds later. She collided with the car at 60 miles per hour, her selected cruise speed, and pressed the brake less than a second before the crash.

It’s not the first time Tesla Autopilot has been the subject of a crash investigation. In March, 38-year-old Apple software engineer Wei “Walter” Huang was involved in a fatal accident with his Tesla Model X engaged in Autopilot, an incident that the National Transportation Safety Board is investigating. A previous fatal crash in May 2016 was investigated by the NHTSA, which cleared Tesla of wrongdoing in January 2017.

Tesla CEO Elon Musk reacted with incredulity to the South Jordan media reports. He wrote to his 21.8 million followers on his Twitter page Monday that “it’s super messed up that a Tesla crash resulting in a broken ankle is front page news and the ~40,000 people who died in US auto accidents alone in past year get almost no coverage.” Musk has spoken before about what he sees as irresponsible media coverage of a feature that could improve safety, telling a reporter in October 2016 that “if, in writing some article that’s negative, you effectively dissuade people from using an autonomous vehicle, you’re killing people.”

In the South Jordan case, the driver was issued with a traffic citation. The administration has not provided a firm end date to its investigation, but its 2016 investigation into the death of Joshua Brown cleared Tesla of any wrongdoing within nine months of the crash.

The police department reminded drivers of semi-autonomous cars in a statement that “it is the driver’s responsibility to stay alert, drive safely, and be in control of the vehicle at all times.”