Police in Ballymena say they fear a spiral of tit-for-tat sectarian attacks after three homes in the town were targeted by petrol bombers this week.
In the latest incident, a woman and her two teenage sons escaped injury after a house in the Millfield area was targeted at about 0100 BST.
The device, which struck a wall, caused scorch damage.
Paint was thrown at the woman's house last week and she has told the police she is considering moving out.
Superintendent Terry Shevlin has appealed for the community's help in stopping the attacks.
"It would appear that there has been a sectarian cycle set up," he said.
"These are totally unacceptable attacks because they could lead to loss of life.
"I am making a direct appeal to community members, that if you are hearing anything please let the police know.
"We will be patrolling the area, we have other operations ongoing, but we do need community assistance on this."
On Saturday, a woman living in the Parklands area of the town escaped injury after her house was targeted, while on Tuesday another family escaped injury after two devices were thrown at their house in Dunfane Park.
Police later said the attack on the house in Dunfane Park had been targeted by mistake.
Ballymena SDLP councillors Declan O'Loan and PJ McAvoy called for the petrol bomb attacks on homes to end before there was loss of life or serious injury.
Sinn Fein councillor Monica Digney said that there was no excuse for the violence which had escalated this week.