“Their mother is being supported by specially trained officers,” the force said.
Police said inquests into their deaths are to take place in due course.
The force previously said it had referred itself to the Independent Office for Police Conduct (IOPC), due to previous contact with the family.
The IOPC said on Tuesday that the previous contact, in August 2023, “related to concerns about a man’s mental health” and determined that an investigation into this previous contact was not required.
The children have been described as “full of life and happiness” by their grieving mother.
In a statement, Angelika Swiderska said: “Piotr was an amazing husband and father to Kacper, Nikodem and Dominik. He loved us with all his heart and would have done anything for us.
“Our boys were happy, active children, full of life and happiness. They were always smiling and even when I looked sad, they would say, ‘Mummy smile like us’.”
