A San Francisco parks worker who ran over a woman as she was sunbathing with her infant daughter and dog last week says that he did not know that he had hit a person until he was arrested by police.

57-year-old Thomas Burnoski was arrested last week after he ran over 35-year-old Christine Svanemyr with the city truck that he was driving through Holly Park in San Francisco.

Burnoski’s attorney, Robert Waggener, said in his written statement about the accident that Burnoski had driven off of a pedestrian path and into the grass in order to avoid an object that was on the pavement, according to the San Francisco Chronicle. His shift was just ending and he was on his way to meet up with other city gardeners at St. Mary’s Park a few blocks away when he ran over Svanemyr.

Upon his arrival at the other park, Burnoski told his supervisor that he thought he had hit something, and that they should go back to check.

They were stopped by police as they made their way back to Holly Park and Burnoski was arrested on suspicion of felony hit and run.

Upon hearing that he had run over a woman, Burnoski was reportedly devastated. Burnoski lamented in his statement that what occurred last week was a “tragic accident.”

Prosecutors have not yet decided what charges will be filed against Burnoski, if any. According to NBC Bay Area, police are still awaiting the results of a toxicology test that will tell them if Burnoski was under the influence at the time of the incident.