A pipe bomb was thrown at one of the houses
Security sources have confirmed the homes of two prison officers in east Belfast were targeted in bomb attacks.
It is suspected that loyalists were behind the attacks.
There were no injuries in either incident.
A pipe bomb was thrown at a house on the Holywood Road in the early hours of Saturday.
A device was also found at a house on Bloomfield Avenue on Sunday.
A woman found the blast bomb in the garden and put it in the bin, not realising what it was.
Police contacted the family after receiving a tip-off that a device had been left at the house.