Three people have escaped injury after arson attacks in the Springfarm estate in Antrim.
At around 10:00 BST bins were pushed up against the front doors of two flats in Tiree Street and set alight, while a burning rag was pushed through a letterbox in nearby Arran Street.
A man and a woman inn one of the flats in Tiree Street and a man in the Arran Street property were not injured.
Police have said they are trying to establish a motive for the attacks.
They have appealed for anyone with information to contact them.
Meanwhile, an unoccupied flat in Alina Gardens, Dunmurry, has been extensively damaged in a separate arson attack.
Neighbouring flats were also smoke damaged. The blaze was reported at about 05:00 BST on Sunday.