A 41-year-old man has been arrested by police investigating allegations of ill-treatment of patients at Muckamore Abbey Hospital.
The man was detained in the Antrim area on Thursday morning. It takes the total number of arrests in relation to the police probe to 35.
Muckamore Abbey Hospital in Antrim provides facilities for adults with special needs and is run by the Belfast Health Trust.
A major police investigation was launched in 2017 after allegations of ill-treatment began to emerge.
It is the biggest criminal investigation of its kind in Northern Ireland with 1,500 suspected crimes discovered in one ward between April and September 2017.
The facility is also currently at the centre of a major public inquiry.
