Three women and a man have been been charged over the alleged mistreatment of eight vulnerable adults at a care home.
The charges follow a lengthy investigation into a number of reported incidents at Hillcroft nursing home in Slyne-with-Hest, Lancaster.
The mistreatment is said to have taken place within the home's challenging behaviour unit, which cares for people with advanced Alzheimer's.
Former employees Darren Smith, 34, Katie Cairns, 26, Carol Moore, 53, and Gemma Pearson, 27, are accused under the Mental Capacity Act 2005 of being a carer involved in the ill-treatment and wilful neglect of a person with lack of capacity.
Lancashire Police said there are a total of 19 charges in relation to eight victims said to have been committed between May 2010 and September last year.
Smith, of Howgill Avenue, Lancaster, is charged with eight offences; Cairns, of Riverview Court, Morecambe; faces four counts; Moore, of Ripon Avenue, Lancaster, is accused of six offences; and Pearson, of Hill Street, Carnforth, is charged with one offence.
All four have been bailed to appear at Lancaster Magistrates' Court on January 3.
A spokeswoman for Lancashire Police said: "Three other people arrested as part of the long-running investigation have been released (with) no further action. They are a 27-year-old man from Morecambe, a 57-year-old woman from Morecambe and a 23-year-old man from Lancaster.
"Another person attended the police station voluntarily and has been released (with) no further action."