BBC News Published image copyrightCambridgeshire Police image captionThe court heard Joshua Gull was having a "mental health crisis" at the time of the offence A man has been jailed for punching a police officer and causing him a serious bleed on the brain. Joshua Gull, 27, hit PC Leo Clarke in Peterborough on 8 February, when the officer was called to the defendant's grandmother's home on his own. Peterborough Crown Court was told PC Clarke had to have surgery and has "life-changing" injuries. Gull, from Oundle in Northamptonshire, was jailed for 20 months after pleading guilty to causing grievous bodily harm. Prosecutor Michael Procter told the court the Cambridgeshire Police officer attended the Ledbury Road property and "from the outset the defendant appear[ed] to be behaving in an aggressive way".