A former British soldier has been arrested by detectives investigating the Bloody Sunday killings in Londonderry in 1972.
Officers from the Police Service of Northern Ireland's Legacy Investigation Branch said they had arrested a 66-year-old man in Co Antrim.
Security sources confirmed the detained pensioner was an ex-soldier.
Thirteen civil rights demonstrators were killed by members of the Parachute Regiment on the streets of Derry in January 1972. Another victim of the shootings died months later.