Secret footage appears to show member of staff 'tickling a murderer' at mental health unit - as BBC's Panorama uncovers alleged mistreatment of patients

The language appearing to have been used by nursing staff to - and about - mental health patients is jarring. "She's a c***t."

"Fat b***h."

Then there is the image of a staff member, lying on a wall outside, appearing to have a nap in the sunshine while on duty.