A petrol bomb has been thrown at a house in Ballymena, County Antrim, the police have said.
One female was treated for the effects of breathing in smoke after the attack on the house in the Chiswick Walk area of Dunclug at about 2200 BST on Sunday.
Police believe it may be linked to trouble in the the Victoria Park and Camberwell areas on Saturday.
Four people were arrested in connection with the disturbances, two of whom remain in custody.
Two other people were released pending reports being sent to the Public Prosecution Service.
A number of weapons - including crossbows - were seized as well as fireworks after the trouble.