Came on orientation, finished the paperwork and was supposed to come the next day but he called and said he has the flu and will come after 2-3 days. He did, we finished everything but did not want to start that day said that he is still sick. The next day said that he has a rash and he is itchy so he took the company car to take a shower and go to the doctor. He did not, he only went to walmart and bought some topical medication. We asked him if he wants to take couple of days off and then start, but he insisted to start driving. He did and by next morning he left the truck on I-55 near Burr Ridge on the ramp saying that he go really sick and needs to go to hospital. We had to recover the truck. Came to the office the next Monday asking to get back to work with hospital gown on, we asked him for a doctor's note to see if he was cleared, he said he doesn't have one. We asked him to wait in the lobby so we can bring the truck at the front so he can get his things, and as he was sitting there started screaming and banging on the door and windows. Because of his erratic and aggressive behavior he had to be escorted from the premises with police/fire department/ambulance. He asked the police to shoot him, and he admitted to the officers that he had schizophrenia and bipolar disorder.