The man who rammed his car into the US consulate in Shanghai late on Thursday night, injuring a guard, was "mentally confused", according to the police. Shanghai police said they had ruled out suggestions the driver had been under the influence of drink or drugs. "During his confession, the driver was mentally confused and rambling," the force said. The black car, with a licence plate from Fujian province, hit the consulate's gate near the junction of Taojiang Road and Wulumuqi Road South in the Xuhui district shortly before 10pm on Thursday night. Police identified the driver as Liu Daojie, 35, of Sanming, in Fujian province. Liu, who was slightly injured in the crash, was caught by guards at the scene. Police quoted Liu as saying: "I have a big company and I've always felt threatened that someone wanted to kill me, so I wanted to stir things up to gain attention. "I was driving from Hangzhou to Shanghai and I saw the security guard and I rammed my car at him." The injured guard, Sun Tao, was taken to hospital and is being treated for injuries to his face, chest and mouth. Investigators found Liu's wife in a guesthouse in Hangzhou. She said Liu had been hallucinating in recent months and hiding at home, believing that someone wanted to kill him. She had taken him to see a doctor, but Liu was told only "not to dwell on things". The wife told police that before driving to Shanghai, Liu had dropped his daughter off at the guesthouse on Thursday morning, telling her he wanted to see a client. He did not return. Photographs circulated on social media showed a barricade in front of the consulate's gate had been damaged by the car. The barrier was later removed by paramilitary police. Another image showed what appeared to be blood on the ground. Mainland reports said security was stepped up following the incident. The area was not cordoned off after the crash and appeared to be calm shortly afterwards.